Dual-Stage Radar Sensor

I started with the excellent article on adding a motion sensor to the BMW alarm. I encourage everyone to read that article first, as I’m not going into enough detail to do the whole job. Consider this as a set of “release notes”. Also, I assume both the BMW alarm and the motion sensor have been installed at this point. Read over all of this first, since I make comments like “connect with to power” then later talk about “put a switch in”. It’s better to do this all at once, but easier to explain using several passes at it. Remember: measure twice, cut once, measure again.

Changes desired from the existing article:

I wanted to use a dual-stage sensor, thus the car would “chirp” when someone got too close to it, before setting the alarm off

I wanted to know which stage sensor had been set-off, by visual inspection (i.e. LED)

I wanted a cutoff switch for both the motion sensor, and the outer stage “chirp”

I wanted to have the sensor be easy(er) to adjust [i.e. not have to pull the car apart to adjust the sensitivity]

I purchased a dual-stage sensor from www.autotoys.com. This sensor is basically the same as the one mentioned in the previous article except that it has two stages of detection and comes with a small piezo buzzer to use as the outside “chirp” sound.

The first thing I did was to decide how I was going to wire everything and and measure everything. Based on other articles and talking with various people, I decided to put the sensor in the center dash, between the seats (under the cassette storage area). After removing the cassette storage bin, I was able to use my pocket knife to lengthen the hole already there to be just long enough to slip the sensor in. I put velcro tape on the sensor and the underside of the dash, and attached the sensor there. This had the advantage of making the screw to adjust the sensitivity easily accessible. I just remove the cassette bin (no tools needed), then use a small screwdriver to adjust the sensitivity. Thus, desire #4 was satisfied.

Next, I wanted an LED to show the status of the sensor. The sensor has an LED already attached to it, a bicolor red/green LED. I simply desodder it, sodder in extension wires, and added the LED to the end of those wires. I was able to snake that new cable (I used heat-shrink tubing to hold the wires together) through the gear-shift area (the shift boot cover comes off easy) and into the blank punch-out button area (which the light for the alarm itself and the glass-breakage sensor already were). I drilled another hole, and used one of the radio-shack LED black plastic covers to give it a professional look. It’s a little crowded there, but still looks good. OK, desire #2 is done.

I needed a place to put the buzzer that was going to serve as my outside warning. I decided it needed to go in the engine compartment, since that was the place the siren was, etc. It’s small so it can go anywhere. I choose up by the drivers wheel, inside the engine compartment. I tie-strapped it into place.

Now I had to find a way to get a couple wires into the interior of the car. If you look where the battery used to go in the ’96 model Z3, in the M roadster there is what looks like a bunch of cables doing just that, but they are fully covered and have a rubber grommet around them. I was able to move the rubber grommet just enough to snake the cables through to the interior. They come out just above the kick-panel speaker in the passenger wheel-well.

OK, this part is from memory (so PLEASE test all your connections before listening to me). I believe I hooked the red wire on the buzzer to the unswitched power supplied to the alarm. The black wire (ground) from the buzzer was attached to the green trigger wire on the motion sensor. I believe when motion is detected, this wire to connected to ground, thus the buzzer goes off.

Now I wanted to install cutoff switches, so I needed a good hidden location. I found one beneath the glove compartment. There is a piece of plastic that goes out from the firewall at a 90 degree angle, that’s what I used. It’s the piece of plastic that has the 2 or 3 plastic turn-screws to keep it on. In the center I was able to cut the holes for the switches themselves. I picked up a couple neat-looking blue auto-switches from a local electronics place and test-fitted them there. Make sure when the switches are in the plastic that there will be enough space to put the piece back on. Some of the tolerances were pretty tight. Now, cut the wire that supplies power to the motion sensor and connect one side to one terminal on one of the switches and the other side of the wire to one of the other terminals. Do the same thing for the cutoff for the “chirping” buzzer. OK, item #3 on my list is done.

OK, one last problem. When the car is running, so was the motion sensor. This has two side effects: the green light keeps going off indicating movement and the outside buzzer is also going off! While driving! This was unacceptable to me.

The solution was to use a relay, like is often used for fog lights and such. Make sure you get a real relay that has both an “87” and “87a” connector (the first one I bought said it had both, but really only had two “87” connections). Basically, you hook power up to the relay and based on whether power is applied to a third connector (or not), passes or does not pass power. The difference between “87” and “87a” is that they are the inverse of each other (one has power when the other doesn’t, and vice-versa).

I don’t remember the details (I’m a computer guy, not an EE), but it should be easy to understand based on the diagrams with the relay. Basically, hook ground an unswitch power directly to the relay. Then the terminal that determines whether power should run or not is hooked to the car’s “switched” power (the violet wire with a white stripe in the alarm harness). Then the terminal that has power with the terminal just mentioned does not have power should be feeding power to the motion sensor. Now, the motion sensor (and the outside buzzer) are only on when the car is switched off!

That’s it!

If you have any questions, you can email me at caslis@netcom.com

Used Airbags

I hope you never have to see your Z3 in this condition, but below are some pictures of a Z3 after its airbags had been deployed. I’m not sure whose Z3 this is; it was parked at a BMW dealership.

This first picture shows the passenger side airbag. It is much larger than I expected it to be. The fabric looks like a thick, almost canvas like surface.

The driver’s side airbag was much smaller, but it looked like someone has pushed part of the bag back into the steering wheel. Looking around the cabin, I expected to see some white powder, but the interior was clean.

What surprised me the most was how little damage there was to the front bumper. I expected to see a lot more damage if the impact was enough to set off the airbags. It is my understanding that the Z3 knows if you are wearing your seat belts or not and will deploy the airbags in a lesser impact if you are not wearing your seat belt. I don’t really know any details, just observing how little damage there was to the front bumper.

///M Roadster Foglight Installation

Pros: Increased visibility, looks
Cons: none?
Cost: Less than $200 installed

As we all know, ///M Roadsters do NOT come with factory foglights as either standard or optional equipment. In order to obtain them, we must look to aftermarket suppliers. The decision as to whether or not I needed them was made for me by virtue of the fact that I live on Cape Cod, which just may be the Fog Capital of the Eastern Seaboard. After seeing Walter’s at the Escape to the Cape Drive this year, I know I would be purchasing a similar model. Walter had chosen PIAA 1400’s in Amber. I opted for the same lights but picked the clear lens version, as they are a bit brighter. I purchased them for $149.95 from 4 Wheel Parts Wholesalers (800-421-1050) as they had the best price.

When they arrived, the only question in my mind was where to mount them. Walter mounted his in the engine intake and they look quite good there. I, however, being the Contrarian that I am, decided to mount them in the outer (brake cooling) intakes. Please note that these lights are very small and should not seriously impede the airflow to the disc brakes.

Wiring these lights was easy, I mean REALLY easy. It should take about 1.5 hours for most anyone.

Step #1 – The switch wires and switch:

The first step is to unravel the wiring harness provided with the foglights. I decided to mount the relay (included) and the fuse holder (also included) in the factory fuse box. This would keep the electronics centrally located and dry. Cut the 2 wires that run to the switch plug about 24 inches from the switch plug itself.

Snake the cut wires through the large grommet already in the firewall on the driver’s side.

Unscrew the fuse holder (remove 2 front screws and loosen 2 read screws) so that you may lift it up.

This will allow some additional access to feed the wires up and through the factory hole in the bottom of the fuse holder.

Once that is done, attach a female spade connector to the input side of the switch wire and (using a fuse tap) connect to the switched side of fuse #44 (note: this photo shows the wire tapped into fuse #33 which is not switched). Attaching the wire to this location will allow the foglights to be turned on whenever the ignition is on. Some locations may require that they be wired in such a way that they may only be turned on when the low beams are on. If this is this case in your area, then you may want to tie this wire into your low beam power wire.

The switch itself was mounted to the knockout panel to the left of the steering wheel where the factory switch is located. I simply trimmed the back of the switch to allow the wire to run straight off the back and I drilled a small hole in the knockout panel. The switch was attached with 2 sided tape. Finally, ground the switch to one of the 4 brass bolts under the driver’s side of the dash (I think they are 7 mm).

Step #2 – The rest of the wiring:

Remember that the entire wiring harness is complete when you buy the kit so the only connections that have to be made are power, ground and any wires you cut during the installation itself.

Re-attached the switch wires that you cut. Run all the ground leads down through the fuse holder and out the front (via the rubber grommet there). Route them towards the factory ground point on the front left fenderwall. They may all be grounded here.

Run the wires for the lights out the same rubber grommet and down towards the front grill. The wires may be hidden in the factory wire-loom. This picture shows the foglight wires hidden inside the factory wire-loom and the ground wires grounded at the factory ground point. At this point, the last wire to connect will be the power wire. It can be connected to the hot side of the fuse box (passenger’s side) below the fuses. You will see a nut than can be unscrewed and the power lead attached. I couldn’t get a good shot of this but you will see what I mean. This is an adequate source of power as the foglight kit has it’s own in-line fuse. Once connected, you may screw the 4 screws back in place that hold the fuse box down.

At this point, all you need to do is wire-tie the relay, in-line fuse and extra wiring neatly together and put the top back on the fuse box.

Step #3 – Mounting the foglights:

Run the foglight wires so that they are just to the driver’s side of their respective brake air intakes. Then, carefully cut a small slice in the plastic (about 8” inside the intake) and pull the wire through. The foglights are attached using 2 sided tape and screws (optional). The 2 sided tape is really strong and should be enough to hold them in place. Plug the foglights into the wiring harness and turn them on. If you installed them correctly, they should work. Turn them off again so they don’t get too hot to handle. Unscrew the mounting plates but don’t remove them. Stick the 2 sided tape to the mounting plate and hold the light in the brake intake duct. With the lights (low beams too) on and shining at a wall, aim the foglights where you want them.

Only concern yourself with the left-to-right angle at this time. When they are pointing where you want them, stick them to the roof of the intake. At this point, you have just mounted the mounting plates. Remove the foglights only and ensure that the mounting plates are firmly attached. If you wish, you may at this time use the screws included with the kit. Re-attach the foglight to the mounting plate and adjust the up-and-down angle before tightening completely. Repeat for the other side and it should look like this.

Step #4 – Enjoy!

They greatly increase your visibility off to the sides of the road as well as in the fog without blinding oncoming traffic. I’m quite pleased with the results – for safety as well as aesthetic reasons.

Wot Guv’nah? ‘Nothah Bleedin’ Project?!?

I know there’s a BMW first-aid kit (51-47-8-163-269) but a few things about it didn’t suit me right. Without any dedicated place in my trunk for it, it’d likely make itself known rolling around back there every time I’d find some corners to attack. It also looked a bit bulkier than I liked. Oh, I’m sure it’s probably outfitted with damn near everything short of a defibrillator..and a nice lawyer-approved Roundel embossed on the leather case…but I’m just looking for something that’ll hold the occasionalBand-Aidd and alcohol wipes for minor scrapes and cuts. Anything more serious and I’ll warm up the PPO medical card.

I filed away a mysterious part number that’s supposed to be a bracket (51-47-8-398-906) for the first-aid kit, but never went to check if this was for the Z3 and if so, where it would take up trunk space. Since manufacturer information was typically sparse and suggested dealer prices are high, I wasn’t about to reward the behavior with a purchase. I struck out to add a practical boo-boo kit to the Z3 — my way…

For this kit I’d suggest obtaining the following items:

Compact first-aid kit. The one I found at Target measures 4″ × 6″ and might’ve cost around $6. It contains a light smattering of adhesive bandages, sponge dressing pads, knuckle bandage, alcohol pads,antisepticc pads, sting relief, iodine packet, adhesive tape roll, gauze, latex gloves and aspirin tablets — all in a sturdy plastic case with better hinges than most kits in this category. I’ve enhanced this kit with some junk-mail samples of PepcidAC, Tylenol and allergy tablets. I’d like to round this out with a quality pair of fold-up metal scissors and some zip-loc bags (medical waste).

Someone told me to look for a liquid bandage. Sounded neat. I found something called New-Skin — antiseptic liquid bandages. These were sold as a box of ten small individual 1.0ml packets. I replaced five of the first-aid kit’s old-tecBand-Aidsds with the New-Skin packets. The New-Skin liquid is supposed to congeal to form a protective barrier against further infection. This appeals to me because traditional Band-Aids would take up 3 inches to protect a 1 inch spot and wouldn’t always stay put.

A package containing 30 inches of each side of Velcro®. (Generically known as Hook & Loop fastener) Look for the sew-on plain-back version. Don’t get the peel-off adhesive-backed version.

And lastly a needle, some thread to match the Velcro and a pair of scissors.

Since most of you will find different-sized kits in your area, I’m only going to emphasize the procedure and omit measurements. I trust you all are competent enough to adapt and extrapolate your sizing without bugging me.

Up on the top right corner of the trunk (behind the driver’s rear wheelwell hump) is a spot begging to be used. I dare say the trunk molding is such that it was meant for something. I’m not sure what the three cut-out ovals are for, but it was a primo opportunity for a fastening point.

I fished a piece of Velcro® through the two middle slats successfully. This tells me I found a suitable mounting point. My first-aid kit was light enough where it’d never cause any weight-related damage to the spot. Now to fashion a Velcro harness. This would secure the kit onto the slats in a manner that allowed quick and easy access. The Shortcut Crowd is probably wondering: ‘Why go through the pain and just simply try to Velcro® the kit to the semi-fuzzy carpeting?’ If you somehow find that to work, congratulations. I, however, don’t consider that secure enough. A few bounces & corners and the carpeting will likely release.

The Velcro® harness I’ve made looks like a sideways “T” when laid flat. It requires stitching together two areas — three if you want to get fancy.

The pieces overlap and get stitched in the manner shown. The “Hook” strip feels harder to the touch. The “Loop” strip is softer and fuzzy. Both strips have a useful and useless side. Pay attention to the orientation of each strip. It would help to look ahead in this article to see how each piece serves it’s purpose. This should allow you to cut the appropriate-length piece. Once you finish the first two critical stitches, that’s it! The project now only needs to be mounted. Start by wrapping the cross-arms of the “T” over and under the boo-boo kit. These tips should overlap and Velcro together.

The long body stem of the “T” simply goes around the box, fishes itself behind those carpeting slats, and comes back around the other side of the box. Tighten up any slack here before Velcro’ing the Hook surface over the fuzzy cross-intersection. The third fancy stitch can be done to the very end of this “T” stem. Fold a half inch of the very end back under itself to cover a bit of the Hook surface. Stitch this closed. This creates a grip tab to start pulling from.

So there you have it; a useful, compact, sturdy boo-boo kit personallized to your needs and occupying a spot in the trunk you’d otherwise never use. If it weren’t for the $5 box of liquid bandage packets, total project cost would be $7.50.

Don’t plan on taking up razor blade juggling? No problem, you can probably find other things to keep in this re-claimed trunk space…emergency CD wallet? snack box? ammo? ant farm? Hey, it’s your space.

Notice: The author assumes no liability nor offers any guarantees your project will go as smoothly or result in the same improvement or usability. Attend a qualified first-aid and CPR class to ensure you administer proper aid to yourself or others. All known issues have been laid down in the clearest manner possible. Despite this, the amount of redundant e-mail sent to the author is expected to be substantial. Not all questions will be answered…some might even get laughed at.

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Direct V1 Power in the 2.8

I wanted a switched direct power source for my V1. I tried to follow the directions for the M Roadster and discovered the 2.8 is wired a little differently. The MZ3 directions called for pulling the lower portion of the dash on the drivers side which I did. This was no easy task and I recommend that you avoid it if at all possible.

After my first failed attempt, I decided to go after the Cell Phone power since I have no plans for installing a phone in the car. I also wanted to try and take the power cord through the passenger side since it seemed like it would be easier.

I followed some of Vince Parsons Directions for locating the cell phone wiring harness by raising the shifter boot cover. It is only held by 2 clips on each side and can be open by pressing on the sides. Wait, what’s this? There is this big piece of foam that wasn’t in Vince’s pictures. No problem, just lift it up to gain access to the inside of the console.

Well I searched and there was no wiring harness to be found. Just the wires for the window switches and hazard lights switch. Went back to Vince’s directions and he mentions that it might be under the carpet beneath the parking brake handle. I found it! Wait, how do get it out of there? I’ll be damned if I know. It’s wedged in there and didn’t want to come out. I didn’t want to remove the entire console so I gave up on trying to get it out.

While peeking in through the OBD door on the passenger side of the console, I had seen an unused wiring harness. I decided that this was going to be my new target power source. Fishing this thing out was not easy because it was wrapped around other bundles of wire but with a little work I had it exposed. I didn’t have much room to work with so I went after the other unused harnesses I saw in there. I found three additional harnesses. I tested for a switched power source and found that the green with white stripe was what I was looking for.

I grabbed the wire tap that came with the V1 and attached it to the wire. I then removed the black plastic panel below and behind the glovebox. It is attached with plastic clips that are removed with the half turn of a flat head screw driver. There is a single one of these plastic clips holding the kick panel covering the speaker at the passengers feet. This provided plenty of room to run the V1 Direct Wire Power Adapter wires. I velcroed the Direct Wire Power Adapter to the top edge of the carpet and used the grounding point next to the speaker.

Next I ran the V1 power wire from the V1 Unit to the Direct Wire Power Adapter. Alan Riley instructed me in the technique of removing the trim along the top and right pillar of the windshield. First remove the pillar piece which just pops off. Then remove the visors. This requires a Star Tool which I just happen to have. Next you must remove the clear plastic cover from the dome light which pops out. Then pop out the light assemble and behind there you will find one more screw to be removed.

Then you can pull down the side that you are working on. In fig. 9 you can see how I wrapped the wire around the dome light wires to keep it from falling out. I then ran the wire down the windshield pillar, beside the dash and door frame where I pushed it behind the insulation and along the bottom of the dash to the Direct Wire Power Adapter.

At this point, hookup the V1 and verify that it works as expected. Now is the time to find out that it doesn’t work. Mine did. Once you have proven that it works, it’s time to reassemble your car. First secure all the loose and excess wires and check one more time to see if it’s still working. Reverse the steps to put all the trim pieces back in their rightful places. When your done you’ll have a direct wired V1 radar detector.

Let’s see John Law try to mess with you now.

BMW Roll Hoops

Pros: Rollover protection, looks great
Cons: Hard to install
Cost: $570 / $602

If your BMW Z3 does not have rollhoops it may be possible to retrofit them into your vehicle. BMW has an upgrade kit that contains the hoops themselves however the hoops can only be retrofitted from into Z3s built on or after 1/97. Specifically 1.9 VIN LB83105 and later; 2.8 VIN LC01377 and later. No earlier production will work.

In addition to the kit you also need to order a replacement set of plastic covers for the rear storage/subwoofer area The cost of the main roll hoop kit is roughly $430 from competitive BMW parts departments that sell over the internet (BMW list price is $640.00). The part number for the main kit is 54-61-9-408-817. The cost of the replacement set of plastic covers varies depending on whether your interior is beige or black, and whether you have the storage compartment or Harmon Kardon subwoofer. See the table below for the additional parts you need and their price. These are the tower covers, side covers for towers, lid for box, small covers where bars go through the lid. With the subwoofer, you will have is the tower covers, side covers for towers, a new lid, and also two brackets and a new subwoofer box.

Please note that the kit for the subwoofer will only work on Z3s with the Harmon Kardon subwoofer. There is not a kit available for Z3s with the “regular” Nokia subwoofer.

Harmon Kardon Subwoofer Storage compartment

Beige interior

51-16-8-407-986 $59.41

51-43-8-407-167 $28.09

51-43-8-407-168 $28.09

51-43-8-407-173 $4.45

51-43-8-407-174 $4.45

65-10-8-407-995 $8.57

65-10-8-407-996 $8.57

Total: $141.63

51-16-8-407-179 $10.01

51-16-8-407-180 $10.01

51-16-8-407-239 $88.72

51-43-8-407-167 $28.09

51-43-8-407-168 $28.09

51-43-8-407-173 $4.45

51-43-8-407-174 $4.45

Total: $173.82

Black interior

51-16-8-407-985 $59.41

51-43-8-407-165 $28.09

51-43-8-407-166 $28.09

51-43-8-407-171 $4.45

51-43-8-407-172 $4.45

65-10-8-407-995 $8.57

65-10-8-407-996 $8.57

Total: $141.63

51-16-8-407-177 $10.01

51-16-8-407-178 $10.01

51-16-8-407-238 $88.72

51-43-8-407-165 $28.09

51-43-8-407-166 $28.09

51-43-8-407-171 $4.45

51-43-8-407-172 $4.45

Total: $173.82

Power for your Radar Detector

I was looking to find a way to hard wire a power connection for my Valentine One radar detector. I had already read through Richard Carlson’s “cutting the cord” article so I felt familiar with the task at hand. This was a great resource, and I recommend you read it first because he has excellent instructions at how to get the plastic panels off, as well as some good warnings. However I wanted the power source to drop from top of the A-Frame rather than up through the dash. The MZ3 has enough room above the rear view for the V1 to slide into (click on the picture for a larger view).

First, a quick lesson about BMW wiring. Turns out that everything is color coded, which makes finding a power source a little easier. Red wires are unswitched power sources (on all the time). Purple (with white stripe) wires are switched power sources (on when the car is on). Brown wires are ground. Depending on which type of power source you want you can choose which wiring harness to use.

The information below is specific for the M roadster’s, it has come to my attention that the wiring on the 1.9 and 2.8 roadsters is different. The color coding is the same but wiring harness locations are different. If you own a 1.9 or 2.8 you’ll want to focus on the area behind your stereo, tapping into its switched (purple and white wire) power source.

A couple M owners spoke with me after using the information below. The first spent about 45 minutes to an hour and commented that everything was straight forward. Thought he could do the job again in less time. The second M owner that spoke to me said the wiring was straight forward but the black plastic trim pieces (under the dash) gave him a lot of trouble. I think he summed it up best by saying “I did it!, but you couldn’t pay me $100 to do it again”.

If you want an unswitched power source there is an unused power connector down by the drivers feet (click on the picture for a larger view). This connector has a positive and a negative unswitched power source. It is in a convenient location just below the speaker. To gain access to this area you will need to remove the lower kick panel and the panels covering the underside of the dash.

Problem was, I was in a picky mood and wanted a switched power source. Under the dash you can locate this connector (BMW calls it X223 – the connector is next to the 40amp fuse strapped to the MAIN wiring harness), it had 5 wires in the connector (click on the picture for a larger view). I know it’s hard to distinguish colors in this picture because of the flash but the left most wire is ground (brown) and the one next to it is switched power (purple with white stripe). In this picture the middle wire is pulled out of the connector (speed sensitive volume connection – another project).

The Valentine One radar detector came with a wiring kit. The black box in this picture is part of that wiring kit. Since this box wasn’t a BMW part the color scheme doesn’t quite match but the red wire out of the box was connected to the purple power source. The black wire was connected to a good grounding point (see the bolt and brown wires next to the speaker)

Once the connection was made all that was left was getting the wire to the radar detector. There was just enough of a gap on the side of the dash to slide a wire back to the corner (like using dental floss). Now the wire had made it to the top of the dash the A-Frame cover just pulls off and you can run the wire under the plastic cover. Along the top you don’t even need to pull off the plastic cover. There is enough of a gap to push the wire in where the plastic piece meets the window.

You should actually work backwards so you have just enough wire sticking out where the radar detector mounts, and bundle up any slack down below where it is easier to hide it.

If you are anywhere near Dallas and would like a trained BMW expert to do work like this for you, I can highly recommend Larry Nissen. Larry did the work on my car and took the time to explain everything for me.

Cutting the Cord

If you’ve got a Z3, chances are you’ve also got a RADAR detector. I’ve got an old BEL detector (no V1 flames please, I know Valentine makes the best detector, but the BEL does just fine for me). I’ve had two problems with the detector placement:

Trying to find a secure place where the detector doesn’t rattle

Trying to find a source of power for the detector

I solved the first problem by simply velcroing the detector to the dash. The problem then becomes the power source. I’ve had the car about four months now and I was getting tired of using the cord to the cigarette lighter. In addition to being unsightly and somewhat rattle-prone, the cigarette lighter is hooked up to unswitched power. This means you need to remember to shut the detector off and turn it on every time you leave and re-enter the car.

Not fun.

I originally thought I could tap into power easily, but it turns out to be quite an ordeal. I tried to get power from the main bank of fuses in the engine compartment, but could not figure out an easy way to run a wire through the firewall. Eventually, I decided to use the power from the head-unit of the stereo and a ground from the cigarette lighter. The job takes about three hours. You need to be somewhat handy, need a working knowledge of automotive electrical connections and must be small enough to crawl into the driver’s footwell. Here’s how you can do it too:

Before you begin.

Get a box or container which you can put the screws in. Figure out some way of labeling the screws, they are all different shapes and sizes. Also make sure you have the 5 digit radio code you will need to reactivate the radio. Expect the job to take 2 to 3 hours. READ ALL DIRECTIONS FIRST!

You’ll need:

a phillips head screwdriver

a wirecutter

two tap-in connectors (Radio Shack 64-3052A)

several miniwire clips (Radio Shack 278-1668)

several connectors (optional – Radio Shack 64-3049A)

a 2mm allen or the BMW tool (a 5/64″ hex key)

at least 2 replacement BMW screw head covers

a seven foot wire to run from your detector to the power source

a white, dry-cleaners type coat hanger

electrical tape

a multimeter (optional,

lots of patience

First prepare the car by taking it apart.

Take the top down.

Look in the driver’s footwell and find two small rubber heads securing the front of the console.

Remove the rubber heads by hooking them with a stout paperclip-end from the bottom (the part that faces down). You should be able to hook them then pull out to remove them. They will resist. Be persistent. This will expose the screw head.

Remove the upper screw first, label it “upper”. Then remove the lower, label it “lower”. (Yes, they are different sizes)

Remove the radio:

Be sure you have the 5 digit reset code to reactivate the radio before you disconnect it.

Flip open the two small doors on either side of the radio to expose a small allen nut (It’s actually not an Allen nut, BMW sells a $16 tool to unscrew it, but a 2mm Allen wrench worked for me).

Screw the nut counterclockwise until it stops.

Repeat with the other allen nut

gently pull the radio towards you.

At the back of the radio, remove the antenna plug

Use a screwdriver to gently push up the “locking collar” for the other connections. It goes up about 1/2 inch, but does not come off. If you do this successfully, the entire back plug unit will come off. Otherwise, gently rock the entire connector back and forth, pulling backwards to remove it.

The radio is now disconnected.

Remove the shift knob by pulling straight up – be careful! You can hit yourself in the nose when it comes loose!

Remove the shifter boot – same process as the hand brake (except the “clips” are on the sides).

Remove the foam collar which surrounds the shift knob (Take a minute to note how it goes back in)

Push from below to pop the lighter out

Crawl under the driver’s dash – you will what looks like two large, black screw heads.

Rotate them 90 degrees and they should fall out.

Now remove the large plastic piece which goes around the pedals. You’ll need to pull it “backwards” (towards the back of the car), then push forwards again to get it loose. I ended up fighting with it for quite a while, but it eventually comes out.

Next, run the wires from the detector to the power source.

Cut the dry-cleaner’s hanger into a bent piece about a foot long. You’ll be using it to snake the wires through the defroster vents

Sitting in the Driver’s seat, start at the right most of the driver’s vents and manipulate the hanger till it comes out of the left most vent.

Tape your detector power plug (connected to the cord) to the hanger and snake it back through the holes.

Use one of the mini-clips to secure it to the dash. This prevents the cord from falling into the vents when not in use.

Run the rest of the wire to the A-pillar.

You can just push the wire into the crack which leads to the door.

Just below the console, pull the trim from the door-sill to allow you to run the wire into the console.

Put the trim back into place

Run the wire along the bottom of the dash, securing it with the mini-wire ties.

Feed the wire up around the side of the center console.

Feed the positive lead to the opening for the head-unit.

Feed the negative (ground) lead to the opening for the lighter.

Now Connect the Wires

If you have plugged in your detector to see how it will fit with the wire you ran, please disconnect it now.

Disclaimer – I used a multi-meter to identify the source of switches positive power for the radio. It was the purple/white wire which leads to the plug. If you have a multi-meter, I would advise double checking on your car. BMW may change the wiring harness from year-to-year.

Use the Tap-in connector to connect the positive line to the purple/white lead of the radio harness. You should immediately hear a little voice telling you that you have just voided your electrical warranty.

Disconnect the lighter from the two wires.

Use the tap-in to connect to the brown (unshielded) lead which runs to the lighter.

If you have a multi-meter, turn the car to Accessory and check for proper power at the detector plug. If you don’t have a meter, you should plug in your detector (risking frying it if you have made the wrong connection).

Now put everything back together

Assuming everything went well with the detector test, you are now ready to close up the patient.

The cigarette lighter is tricky to get back in. Before reconnecting it and reinserting it, you must first move the orange collar from the top to the bottom of the unit.

You do this by pushing out (from the inside of the unit) on both the little “wings” at the same time. This requires a little manual dexterity or a lovely assistant.

Once you do this, you can move the orange ring down to the bottom of the unit:

Reconnect the wires to the lighter unit.

Insert the unit into the dash, aligning the small cutout on the left with the tab of the orange collar.

Press in on the collar, it will seat itself, then press the lighter in which will also seat itself.

Before putting the shifter back together, turn on the lights and make sure the small bulb which illuminates the lighter is still in place. If not, re-seat it (it goes to the right of the lighter when looking at it from above, it just fits into a small hole next to the lighter.)

Reinstall the foam collar, shift boot and knob.

Reconnect the head-unit and put it back into the dash, securing with the allen wrench.

Re-screw the console screws and put the new screw heads on.

Reinstall the foot-pedal guards.

That’s it! You can now connect your detector, it will turn on when the ignition is turned on. Now go find your cigarette lighter (or lighter plug) and put it back in! You’ve cut the cord!

Adding Motion Sensor to BMW Alarm

Here is what I did – it is fairly straight forward but please make modifications at your own risk.

The sensor I used came from Sound Conceptions – “www.autotoys.com”. The sensor is listed as “sensor: single zone perimeter sensor (radar)” and is $24.95 as of today (3/30/98). You can find it in the storefront – security section. It has three wires to hook it up – battery, ground and trigger. The wires are just long enough to reach where I mounted the sensor. If you want to experiment with different mounting locations, you may want to extend the wires.

For safety, unplug the BMW alarm harness at both ends before making any connections. I soldered and taped all connections.


connect this to the fused battery wire in the alarm wiring harness this is a yellow wire with an inline fuse. Connect to the alarm side of the fuse, thus the fuse protects the new wiring.


connect this to the ground wire in the harness – brown wire.


this will get connected to the hood switch sensor wire (white with red stripe) in the wiring harness. To avoid potential interference between the new and old sensor – I isolated them with two diodes. The diodes are 1N4001 which you can get at Radio Shack. Cut the existing sensor wire and splice in a diode with the cathode (banded end) toward the sensor – this sensor is active low. On the alarm side of this diode, add another with the banded side toward the new sensor – connect the new sensor trigger wire to the cathode of this diode. See the crude diagram below:

I mounted the sensor in the console just forward of the gear shift. Remove the gear shift boot and the foam insert. If you put just the hook portion of some stick on velcro tape on the back of the sensor, you can stick it to the carpeting under the console. You will want to play with the sensitivity adjustment on the sensor. I have mine currently set about 3/4 of the way to fully sensitive.

Performance is good but a little inconsistent. If someone sits in your car, the alarm will definitely go off. An arm reaching in will set off the alarm if the arm is moved around. Repositioning the sensor might help – the directions say the higher it is in the car the better.

Discuss this article and other Safety/Security upgrades in the

///MZ3.Net discussion forum.

HMS Rollbar

Pros: Rollover protection, aggressive look
Cons: Hard to install, occupies windscreen mounting location
Cost: $700

I had the pleasure of attending the 1997 Z3 Reunion. At this reunion I got to watch a video of Z3’s being crash tested. I was very impressed with Z3’s ability to protect the driver in an accident in all but one of the tests… the rollover.

I think my paranoia started there watching that video, but it was only a slight paranoia because I could tell myself “how would you ever roll a Z3”. Later I remembered a story I heard about six months before the reunion. A Z3 owner was rear ended by a pickup truck going about 40mph. The pickup smacked into the back of the Z3 and crunched it pretty good, but the truck didn’t stop when it hit the bumper. The truck’s bumper hit the Z3 at about mid-trunk and basically jumped up onto the trunk and eventually stopped about a foot and a half behind the drivers head. If the truck had been going any faster it might have driven right into the back of the driver’s head because there was nothing to stop it.

That was it, now my paranoia was real. I started noticing how many big pickups, and surburbans there were in Dallas and it was starting to really spook me every time one got behind me. Okay I’m exaggerating a little but my paranoia was real and it was taking away from the enjoyment of driving.

I have a 1997 Z3, starting with the 1998 models BMW added rollbars as a standard feature (well really they’re roll-hoops not rollbars but basically the same thing PROTECTION). As a ’97 owner I really only had one option and that was HMS Motorsport (Z3s built on or after 1/1/97 can get the rollhoops). The owner of HMS also owns a Z3, so he took the time and capital to design a rollbar specifically for the BMW Z3. The design is top notch with an emphasis on racing and safety.

Once I had the rollbar ordered and delivered I was left with the small task of installing it. Thankfully I had several friends who helped me do the installation (which really wasn’t nearly as difficult as I thought it would be).

So now my Z3 has rollbar installed and I am extremely pleased with it. I think it adds an aggressive look to Z3 and more importantly protects Robert from that evil suburban. I like the appearance but it does change the Z3’s looks quite a bit and some may not care for the more aggressive look.

Sold By:

HMS Motorsport


(888) HMS-3BMW