Inside rear view mirror

[BigBird05]

Does anybody have the wiring diagram for a 2003 rear view mirror?

[hatzie]

What options on your mirror?

[BigBird05]

2003 Yukon with comp and temp.

[hatzie]

Tomorrow or Monday I'll be back home for more than 2 minutes.
I'll dig up the diagrams in the 05 service manuals. Assuming the Pickup trucks are the same as the SUV in this regard. Not everything is the same between them. Helm lists separate service manuals for the SUV and the Pickups.

[biketopia]

here you go

[BigBird05]

Thanks. So I hooked up the + and - the ambient air sensor and it didn't light up. Any ideas?

[hatzie]

Recheck your connections.

If the schematics are correct...

6 should run to the A terminal on the air temp sensor.
7 should run to the B terminal on the air temp sensor.

8 should be chassis ground.
13 should be ignition power.

Power and ground are easy.
You can ohm out the temp sensor wires with long test leads the proper probe terminals to make sure each side connects from the mirror all the way to the sensor.

[biketopia]

whops missed the initial follow up, but to hatzie's comment he is spot on. And the diagram is for an 03 yukon.

[BigBird05]

I have it on the bench right now. I'm going to plug it into the Yukon wiring connector and see if it lights up. If It does then I will buy a new ambient temp sensor.

[hatzie]

Originally Posted by BigBird05

I have it on the bench right now. I'm going to plug it into the Yukon wiring connector and see if it lights up. If It does then I will buy a new ambient temp sensor.

Was the mirror dead or something else going on?

These are Gentex mirrors made for GM.
The sensor polarity may actually make a difference. I'd be sure to run Sensor plug B to mirror 6 and Sensor plug A to mirror 7.

[hatzie]

GM service manual captures.
The GM wiring diagram should be valid for the 03-05 trucks. Maybe the 06 & 07 classic as well.
The DF5 ambient temp sensor symbol is for a regular thermistor.

These are connector end views for the mirror and the ambient temp sensor.

[BigBird05]

Thanks everybody for the help. After bench testing 3 mirrors and not getting them to work. I went out an plugged them into my Yukon. All 3 still don't work. Guess I'll get another on my next trip to the salvage yad.

[hatzie]

The Gentex mirrors have issues with cracking solder joints on several of the larger SMT resistors just like the instrument clusters on these trucks.

Gentex used a super thin PC board similar to the thin PC boards that GM used in the digital climate control heads.
If you don't have significant experience with electronics repairs of this type I would not start with one of these mirrors. You can easily make an un-repairable mess.

Before you pitch them I might actually be interested in repairng them.

[hatzie]

They arrived yesterday.
I always do a visual check under the microscope for obvious problems.
First the power regulation & microchips. Then I check the display interconnect, SMT resistors, and harness plug connections to the PC boards for cracked solder joints.

I opened all three of them up last night to take a quick look and take some pictures with my microscope camera that arrived yesterday as well. It works very well. Now I can take pics to show what I've found when looking at boards.
The components in the pictures look big but I can't read most of the markings without my microscope.
I won't have time to sit down and work on them til Saturday or Sunday.

The Compass/Temp mirror has a cratered TO252 78M05 SMT 5v linear voltage regulator. Usually this comes from reverse polarity on the power input or shorts on the output legs.
You can see the hole where the magic smoke escaped from the damaged 78M05 regulator.
I'll have to investigate to see what blew it up before replacing it.

This is an undamaged 78M05 on one of the other mirror boards.


The two Onstar temp compass mirrors have cracked solder joints on resistors and most of the display board interconnect header joints as well as several cracked joints on the connector for the cab harness... Business as usual.

[hatzie]

This is one of the mirrors opened up with the compass under the mount cover disconnected.

The cab harness disconnect terminal numbers;

• Lower Right terminal 1
• Lower Left terminal 9
• Upper Right terminal 8
• Upper Left terminal 16

**EDIT**
I decided the trailer wheel bearings could wait til it's somewhat above 5°F.
I re-flowed the display daughterboard interconnect on both sides, all 16 pins on the main connector, and various resistors.

This is my power pak hookup using GT150 terminals. Set 250MA current limit 12.6V from my bench supply. Ground to terminal 8 & Hot to terminal 13.

This is the mirror powered up without my calibrated resistors on the temp sensor lines.