Electrical question -- Javier?!?

[Kalevera]

Guys...

Picked up a Gentex 187 autodimming rearview on eBay for $12. Got the new button, mirror glue, pulled the old button (and removed a bit of my windshield with it) and I've got the new mirror physically installed.

BUT! I'm getting no power to the wiring harness. I checked the continuity by snagging a bulb out of the dome light...nothing with ignition on/engine running, on any of the leads. It also looks like the ground isn't connected as taking power from the dome light and using the harness ground doesn't complete the circuit.

My understanding of this is that fuse 30 runs the power to it. All fuses in the rear power dist box are fine, and my windows/all other accessories work. The wiring harness is a 6 pin connector with two banks of 3 and 3 wires - 1 brown, 1 blue, 1 gray (?). My Bentley's lists the blue as being the ignition. The mirror has no reverse wiring in its harness and the unit works fine without it.

I've been thinking about just tapping it into one of the dome lights, but that would be a pain, and I'd like to use the wiring as the engineers intended it to be used.

So how do I troubleshoot this thing? Is it as simple as me not plugging in the other end somewhere? The harness disappears into the electrical tape covering the sunroof, dome light, and vanity mirror wiring.

Best, whit

[Javier]

In your post, there are some sentences I couldn't understand. May you explain?

BUT! I'm getting no power to the wiring harness. Which connector?

The wiring harness is a 6 pin connector with two banks of 3 and 3 wires - 1 brown, 1 blue, 1 gray (?). 6 wires or 3? Again which connector? Did you unplug it from anywhere?

The mirror has no reverse wiring in its harness and the unit works fine without it. What do you mean reverse wiring? Mirror should have 3 wires, if per BMW spec.

So far, 1990 drawings do not show automatic inside mirror, 1992 does, so used some info from 1992 and some from 1990 to offer you.

In 1992, mirror is connected to X360 (3 pins black). This same connector is shown as "Not used" in 1990 drawings for Fuse F30 details. A Red/Green wire feeds all loads from F30, including pin 2 at X360, both 1992 and 1990 models.

Also, 1990 drawings show a brown wire from pin 1 of X360 for ground connection X492. It is also marked as "Not used".

Lights switch details drawing for 1990 also shows a Gray/Black wire coming from light switch and energized in positions I and II, going to pin 3 of X360 connector. It is also marked as "Not used".

This are the 3 wires intended for automatic inside mirror, 1=Ground, 2=Power, 3=Lights ON signal.

The funniest thing is that this connector is not supposed to be in the center of the roof, at the interior lights location, but behind the Make up lights at the Left side (Drivers side for US).

Just let me know if this helps, and if I can be of further assistance.

Javier

[Kalevera]

Hi Javier. Thanks for the reply. Here's what I've got:

In your post, there are some sentences I couldn't understand. May you explain?

BUT! I'm getting no power to the wiring harness. Which connector?

This is the connector that's built into the car. The new Gentex mirror and accompanying wiring work fine....it's just figuring out how to get power to it from the car.

The wiring harness is a 6 pin connector with two banks of 3 and 3 wires - 1 brown, 1 blue, 1 gray (?). 6 wires or 3? Again which connector? Did you unplug it from anywhere?

This thing was sitting behind the sunroof panel/dome light, doesn't look like it was ever connected to anything...I did pull it from the pass side a bit. It's a black connector with a white plastic (removable) cover and had about 6 inches of wire on it. The connector has 6 spots, but only three have wires to them. Since the early e34's could be had with an autodip mirror, I figured that this was the wiring for it, already sitting there.

It is my understanding that electrochromatic mirrors have a ground, ignition, and a "reverse" lead. In this case, the wiring supplied with the mirror only has ground and ignition, and I can run a wire from the mirror to the car for the reverse if necessary (but the mirror works fine without it).

The mirror has no reverse wiring in its harness and the unit works fine without it. What do you mean reverse wiring? Mirror should have 3 wires, if per BMW spec.

So far, 1990 drawings do not show automatic inside mirror, 1992 does, so used some info from 1992 and some from 1990 to offer you.

In 1992, mirror is connected to X360 (3 pins black). This same connector is shown as "Not used" in 1990 drawings for Fuse F30 details. A Red/Green wire feeds all loads from F30, including pin 2 at X360, both 1992 and 1990 models.

Also, 1990 drawings show a brown wire from pin 1 of X360 for ground connection X492. It is also marked as "Not used".

Lights switch details drawing for 1990 also shows a Gray/Black wire coming from light switch and energized in positions I and II, going to pin 3 of X360 connector. It is also marked as "Not used".

This are the 3 wires intended for automatic inside mirror, 1=Ground, 2=Power, 3=Lights ON signal.

The funniest thing is that this connector is not supposed to be in the center of the roof, at the interior lights location, but behind the Make up lights at the Left side (Drivers side for US).

Just let me know if this helps, and if I can be of further assistance.

Javier

What does "not used" mean? I noticed from my Bentley's that "not used" fuse holders have physical barriers in place to prevent inserting a fuse, nor (of course) is there any wiring around them.

I assume that, since the wiring is there for the auto mirror, it simply isn't connected somewhere.

In looking at the Bentley schematics between the 1990 and 1992 years, it seems like it should work. Practically the same wiring.

What/where is X360? X492?

Best, Whit

[Javier]

it is a Lights On signal.

The connector for the Automatic interior mirror is not located behind the sunroof panel/dome light in 1990, as I said, it is located behind Make Up lights at Drivers side, it's a black, 3 position connector, with Brown, Red/Green, and Gray/Black wires.

Check for the connector, should be there, guess not used means nothing plugged.

X360 is the name of the connector I described/Located for you (per drawings), X492 is the name of the ground post, located near the Rear Power Distribution Box. Brown wire comes from there.

1990 and 1992 are very similar, but connectors may not be located in the same places, 1992 drawing is all mixed up, and report X360 at the trunk lid!!!!

Javier

[Kalevera]

Thanks again for all the info.

I pulled the makeup light, visor and visor mount but couldn't find another free harness. I tried the pass side as well with no luck. The only free connector in the vicinity, so far as I can see, is this 6 pin thing. I checked the colors of the wires on the free connector: blue/green, blue/purple, and brown/red...all have white "spots" on them. Maybe the schematic is different for my car? Do you have a pic of the 1990 harness for that area? I can't find one in the ETK...

Best, whit

[Kalevera]

Problem solved! Thanks Javier -- of course, you are right. There is a 3 pin connector up there. Mine was white, had the colored wires as described. The thing was stuck in there, which probably explains why I couldn't see it last night in the dark.

I ended up wiring the mirror to the "lights on" lead; logic being that my lights will be on anytime I'll need autodimming. Also, it appears that the red ignition wire is hot at all times, so I didn't want to have to turn the mirror on and off every time I use the car at night.

Now the only question that remains is...what is that other harness for? Maybe the alarm transponder?

Thanks!

best, whit

[Javier]

up there, so it makes sense.

Yes you are right on your decision. BMW uses F32 to feed power to the motor, but control circuit (on/off decision) is powered with the "Lights on" signal.

Javier

Edit: Only concern may be power drawn, but guess the mirror motor should be insignificant.

[Kalevera]

If it's on a 7.5 amp fuse, I should be okay...think that's what it is, but time will tell.