Electrical modifications

[patrick]

So what are some of the cool modifications you guys have made to your cars' electrical systems.

This is what I've done to my '86 528e.

- Built a 14 gauge wiring harness with fused relays to power overwattage euro headlights.

- Set up the rear fog lights to be additional brake lights.

- Taken power from pin 9 (hot in run or start) at the headlight switch to pin 2 at the fog light switch, so I can turn on my fog lights (which aren't really fog lights any more, but are Hella 530 driving lights) any time the key is on.

- Removed the stock ground from pin 85 on the fog light relay, which is connected to pin 87 on the high beam relay, and spliced it to pin 85 on the high beam relay. (The fog light relay is grounded through the high beam filaments from BMW. When you turn on the high beams, the ground side of the fog light relay sees system voltage on both pins 86 and 87, so there's no voltage difference, so the relay disengages. Now I can leave my driving lights on with my high beams.)

- Set up a 4 wire heated oxygen sensor to replace the 1 wire unheated oxygen sensor. See http://www.mye28.com/viewtopic.php?t=13514

- Bypassed my flaky interior light control module by jumpering the brown/violet wire (grounds through door switches) to the brown/red wire coming from the interior light switch. So when the switch is off, the lights are off. When the switch is on, the lights are on. When the switch is in the middle, instead of the light control module deciding what's up, the car is old school. Lights on with any door open. Lights off with all doors closed.

- Another fog light switch is going in the blank spot where the headlight aiming switch goes in the euro cars. This switch will be wired to the brake lights. I will have the option of having the brake lights on or not. I will use the interior light control switch in the second fog light switch to turn the ABS on or off.

Okay, what have you guys done?

Patrick

[RonW]

A few things:

1. A new stereo, which bypassed the old BMW amp. I also added a CD changer in the trunk. I ran new speaker wires from the head unit to the trunk, and created my own ad hoc connector standard from Digi-Key parts, so if I want, I can restore the old amp- or add a new one- with a minimum of fuss.

2. A keyless entry system from JC Whitney. This is the I.C. Dynamics Valiant 2RTA, which has three buttons, one of which is for a trunk release, which isn't applicable to the e28. I used that 3rd button to turn on the interior lights. Thanks to the e28's timing unit, the lights stay on for about 6 seconds after I release the button. No reason to do this really; it was just something to do with nearby light wire that became active once I intalled this:

3. When I open any door, even with the car off, the power windows become active. This lets me raise or lower the windows without turning on the car. This feature was not enabled in U.S. cars. There's an empty relay socket, into which you you put a 4-pin relay, just like all the onther 4-pin relays in your car. You also have to track down a couple of wires that run from that socket to the footwell speaker cavities. The wires aren't connected to anything. You want to connect one of them to the door switch, and isolate the other so it doesn't short on anything. Or do as I did and wire it to the keyless so you can control the interior light remotely.

4. Headlight warning. I added a 4-pin relay with a diode, and wired it so that if I leave my parking lights on (or headlights, by implication) the e28's warning chime goes off. This has paid for itself many times over. Here's a PDF explaining how to do it.

5. Instrument cluster now has external NiCd batteries, for ease of replacement.

[Mless5]

1. Stereo
2. Rear fog added
3. Battery "-" replaced with 0ga
4. All grounds under the hood replaced with 4ga
5. Euro operation of headlights.

[BMWCCA2]

Now I can leave my driving lights on with my high beams.)

Which is illegal in every state I've ever live in, so be careful, or simply swap it back once a year. Most states have a limit as to how many headlamps can be lit at one time. In Virginia, that's four and fogs count.

[lkfoster]

1. Replaced stereo and amplifier with Blaupunkt CD head unit and with pre-amp feed to a Sony 4x30W amp.
2. Added rear fog light using euro switch and dash indicator.
3. Rewired front fog switch to be active with the parking lights.
4. Added turn signal side repeaters.
5. Euro code Hella lights. Don't remember if I have 100w high beams or the oem 55w, it's been ages since I did this.

[Mike W.]

Which is illegal in every state I've ever live in, so be careful, or simply swap it back once a year. Most states have a limit as to how many headlamps can be lit at one time. In Virginia, that's four and fogs count.

While I don't know Virginia's laws, I think you are forgetting driving lights are kind of the opposite of fog lights, they are to supplement high beams and project waaaaay down the road. So it would be counterproductive to have them on any other time than besides when the highs are on.

Driving lights can be, nice, I had them on an old VW one time, but with California pushing 40 million people now, it's rare I even get to use my high beams except to flash some SOB using them in traffic when he shouldn't.

[Blue Shadow]

1)Installed rear fog/brake lights with dash switch to select with the correct rear fog telltale on with the fogs only.
2)Installed all different stereo with antenna defeat switch (older color correct alpine HU without the antenna defeat built in) using the two button fog light in the fader position.
3)Used other half of that switch to control the amps fan as the fan is only needed in the summer during a trip.
4)Installed a gong defeat switch identical to the rear window defeat switch opposite said switch where there is a cutout.
5)Installed a lock-unlock button on the other side of the radio using an unlighted window switch. Lighted switches don't work.
6)Upgraded to air horns.
7)Installed the M+N two gauge panel in place of the ashtray with color-matched red backlighted VDO gauges.
8)Installed euro lamps and euro connectors for those lamps using the H-4 low beam and high beam filaments as specified by the hi beam switch.
9)Tinted side marker and front turn signals.
10)Lighted window switches, but who hasn't (pre-'86).
11)Hardwired radar dectector.
12)Windows operate with the door open, Euro-style. Please do not tell the US lawyers.
13)Seat heaters are on the way
14)Upgraded turn signal indicators shown:

[RonW]

Windows operate with the door open, Euro-style. Please do not tell the US lawyers.

OK, that's a new one. What might the lawyers have to say about it?

[EuroShark]

"12)Windows operate with the door open, Euro-style. Please do not tell the US lawyers."

Mine do this and I have not touched them.

[Skeen]

"12)Windows operate with the door open, Euro-style. Please do not tell the US lawyers."

Mine do this and I have not touched them.

Do they do that without the key in the ignition (at run/start)?

[EuroShark]

No, just with the doors open and the key in the ignition in the on position. I was under the impression that they are supposed to work this way? Haha, every other car I have had works this way...

[BMWCCA2]

BMW changed that feature way back on the E3 sedans to comply with U.S. safety regulations. Leave your windows down and it starts raining, run out, open door, roll up windows without the key. I guess if you leave your kids in the car they might get stuck in the window foolin' around. What a country. A feature I like in the E34 that would be nice to have in the E28 is the windows and sunroof still operate after turning the car off until you open the door.

[RetiredDoc]

I added a switch to shut off my brake lights and my tail lights while running from the police.

You didn't limit your question to the e28.

I did this electrial modification as a 16 year old high school delinquent during the time I spent drag racing on public roads.

I haven't done any meaningful electrical modifications on the e28. It's basically stock except for Hella headlights and lighted window switches.

[Blue Shadow]

Well Ron, you probably read why I put that disclaimer about the lawyers. It was your post that gave me the instructions to do this change. Thanks again.

[RonW]

Well Ron, you probably read why I put that disclaimer about the lawyers. It was your post that gave me the instructions to do this change. Thanks again.

I was wondering about the disclaimer.

I guess if you leave your kids in the car they might get stuck in the window foolin' around. What a country.

With the doors closed, the windows don't operate. But I guess it's OK to have a deadbolt system that lets you lock people into your car so they can't get out? The last time I tried that thing it malfunctioned, so I couldn't unlock the car. I ended up having to get a new lock cylinder. If there were people in the car at the time, I'm sure they'd think their predicament was hilarious.

[Kmoy2002]

So what are some of the cool modifications you guys have made to your cars' electrical systems.

This is what I've done to my '86 528e.

- Taken power from pin 9 (hot in run or start) at the headlight switch to pin 2 at the fog light switch, so I can turn on my fog lights (which aren't really fog lights any more, but are Hella 530 driving lights) any time the key is on.

- Set up the rear fog lights to be additional brake lights.

Okay, what have you guys done?

Patrick

Those ^ along with 2 ambient overhead LED's similar to those on newer BMW's, bypassed amp + rewired stereo, Custom AUX/ipod interface integrated into ashtray.

[BillW]

1. Foglight switch near the radio powers it without the key. OBC also come on.

2. A similar switch goes to a hidden garage door opener. Modified it for temporary-on.

3. Door chime cutoff switch under the dash.

4. Front running lights (in bumper) eliminated so as not to compete with City lights . Still operate as turn signals.

[a]

my mods are mostly just shade tree repairs. Ive retro-fitted 4 position blade fuse blocks onto 3 528es, the Grape has 7 blade fuses. The Grape also has a starter button grafted in. The rest is just labeling. I have painted pins 11 and 14 on the diag port with white paint so the starter can be jumped easily with a piece of 12awg I keep on the radiator. I have labelled the main and fuel pump relays and their spares for easy swappage by the spousal unit. I have recorded the radio codes in the owners manuals and on the radios themselves. I fixed Swarz's IP by replacing the dead SII batteries with remote nicads.

[patrick]

I have recorded the radio codes in the owners manuals and on the radios themselves.

Ha! I used to do that when I worked as an Audi/VW tech. Any time I had to pull a radio out of the dash to find the serial number so I could dig up the radio code for someone, and every new car I PDIed, I would write the radio code on top of the radio with a Sharpie, just because it is SUCH a pain in the ass to get the manufacturer to give it up, even if you're working at a dealer.

Patrick

[RonW]

I have recorded the radio codes in the owners manuals and on the radios themselves.

Ha! I used to do that when I worked as an Audi/VW tech. Any time I had to pull a radio out of the dash to find the serial number so I could dig up the radio code for someone, and every new car I PDIed, I would write the radio code on top of the radio with a Sharpie, just because it is SUCH a pain in the ass to get the manufacturer to give it up, even if you're working at a dealer.

Patrick

But... but... then if someone STOLE one of those radios they could... (Did anyone ever steal one of those radios?)

[patrick]

But... but... then if someone STOLE one of those radios they could... (Did anyone ever steal one of those radios?)

Who would be dumb enough to steal a stock radio? Everyone knows you need the radio code to make them work.

Patrick

[DRP535]

A few things:

3. When I open any door, even with the car off, the power windows become active. This lets me raise or lower the windows without turning on the car. This feature was not enabled in U.S. cars. There's an empty relay socket, into which you you put a 4-pin relay, just like all the onther 4-pin relays in your car. You also have to track down a couple of wires that run from that socket to the footwell speaker cavities. The wires aren't connected to anything. You want to connect one of them to the door switch, and isolate the other so it doesn't short on anything.

This was also disabled on Australian cars. The correct operation however is for the electric windows to be operational only when either of the front doors are open. It should not operate with the back doors opened if the fronts are closed. As you described, all that's required to enable it is to fit a relay they deleted to a socket hanging down under the steering column and to replace the front door jamb switches with dual pole versions of same which are listed in the ETK or on RealOEM. All the wiring and plugs are already in place in the cars so you do not need to do any insulating, soldering or re-wiring to anything. Just plug the unused plug ends into the blade connectors of the dual pole switches and you're done.

[DRP535]

1) Added accessory power from Check Control panel to power M-Tech mirror with map reading lights a-la M5

2) Added accessory power from ashtray to gear lever to power illuminated gearknob a-la E30 M3 Sport Evolution

3) Added dual pole door jamb switches for proper Euro operation of electric windows without key

4) Replaced stereo and ran new speaker wires to front footwell speaker locations

5) Added new speaker wires up to front door mirror mount tweeter locations and installed tweeters.

6) Installed Cobra remote car alarm wired into central locking.

7) Rewired sunroof power so it operates only on key rather than always which is how it was wired - don't know why

8) Added (and then subsequently removed again) radar redector wired directly into fuse box.

9) Replaced mobile phone charger operation LED from green to amber so it matched the rest of the interior lighting :-)

10) Replaced sunroof switch with illuminated type

11) Replaced rear 5.1/4" rear speakers maintaining original ITT tweeters. Reused old capacitor for x-over.

Haven't needed to do anything to the operation of headlights or foglights front or rear. These have not been butchered like on the US cars. All operates like it should with individual swtiches for front and rear fogs plus parking function for side to side parking lights.

[a]

hmmn, there is a little brass hoopis that is wye shaped and has 3 male push ons on it. You could use that instead of sourcing the dual blade door switch

[RonW]

This was also disabled on Australian cars. The correct operation however is for the electric windows to be operational only when either of the front doors are open. It should not operate with the back doors opened if the fronts are closed. As you described, all that's required to enable it is to fit a relay they deleted to a socket hanging down under the steering column and to replace the front door jamb switches with dual pole versions of same which are listed in the ETK or on RealOEM. All the wiring and plugs are already in place in the cars so you do not need to do any insulating, soldering or re-wiring to anything. Just plug the unused plug ends into the blade connectors of the dual pole switches and you're done.

On US cars, the driver's door already has the dual pole switch. One pole is used for the interior lights, and is wired to all the other (single pole) door switches. The other pole is for the ignition key warning. The simplest thing for me to do was wire the window feature into the interior light wire on the driver's door. (For my daily driver I spliced it. For my nice 535is I made a Y.) That made it work for all doors using one wire. I connected the remaining wire the unused trunk output from my keyless unit, so now if I hold that button down on the fob, the lights turn on, and someone inside the car can raise or lower the windows.

hmmn, there is a little brass hoopis that is wye shaped and has 3 male push ons on it. You could use that instead of sourcing the dual blade door switch

I tried them. They take up too much space and make the switch not work. I ended up making a Y out of regular spade connectors and wire.

[RonW]

A few more I forgot about:

-OBC display backlight replaced with LEDs.

-Rearview mirror with map lights. Map lights disabled if car off.

-Replaced plastic accessory fuse box mount with corresponding metal bracket from 1988 528e, which mounts to rear of power distribution box, and is more durable.

-On my '86 535i: Added a brake light relay. This was an attempt to fix intermittent cruise control- the lights, and cruise control servo, are grounded when not braking. (The cruise control works well now, but I don't think this relay was the fix.)

-On my '87 535is: Replaced the interior light delay unit 61 31 1 373 975 with 61 31 1 373 974, which does not require the driver's door handle to be lifted to enable the delay feature. Opening any door enables the delay.

[DRP535]

[The other pole is for the ignition key warning.

What is this ignition key warning of which you speak?

[a]

lets you know when you left the key in the ignition and you opened the driver's door. I de-bonged the Borman6 yrs ago by unplugging it.

[DRP535]

Map lights disabled if car off.

I thought about wiring it this way too but decided against it. I figure I'm most likely to be wanting to look at a map at night in the car with the engine switched off so I'm not feeling rushed about figuring my way so wired the mirror in to the always hot red wire into the check control panel. In other cars the map reading lights work without the key as well including my E32 740iL so figured this was the "right" way of doing it. I would be interested to know how it operates in an M5 from the factory.

Replaced the interior light delay unit 61 31 1 373 975 with 61 31 1 373 974, which does not require the driver's door handle to be lifted to enable the delay feature. Opening any door enables the delay.

This sounds interesting. Tell me more.

[lkfoster]

I thought about wiring it this way too but decided against it. I figure I'm most likely to be wanting to look at a map at night in the car with the engine switched off so I'm not feeling rushed about figuring my way so wired the mirror in to the always hot red wire into the check control panel. In other cars the map reading lights work without the key as well including my E32 740iL so figured this was the "right" way of doing it. I would be interested to know how it operates in an M5 from the factory.

My USA M5 map lights don't work without the key.