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Hello all!
New to the forum and the Vette world, loving my new C5!
I noticed that the previous owner had the rearview mirror unplugged, so naturally I plugged it in.
Now the lights come on (dull amber in the middle and the two reading lights) however they will not go off.
I did google the forum and found some hits about the dimmer switch under the HUD controls but mine is not in "parade" mode. I did try all sorts of positions, max light, min light, **** in/out but nothing will make them go off.
They also keep the foot well lamps lit.
Hello all!
New to the forum and the Vette world, loving my new C5!
I noticed that the previous owner had the rearview mirror unplugged, so naturally I plugged it in.
Now the lights come on (dull amber in the middle and the two reading lights) however they will not go off.
I did google the forum and found some hits about the dimmer switch under the HUD controls but mine is not in "parade" mode. I did try all sorts of positions, max light, min light, **** in/out but nothing will make them go off.
They also keep the foot well lamps lit.
Would love some help!
Strange that the rear courtesy lamps are not also illuminated. The footwell and rear courtesy lamps, and the inside rear view mirror lights are controlled by relay 42 in IP electrical center. All you need is a test light or DMM to troubleshoot.
What does it say about the mirror in your owner's manual?
With entry lighting, the interior lamps will come on when
entering the vehicle for up to 20 seconds. With exit
lighting, the interior lamps will come on when the key is
turned to OFF or a door is ajar for about 20 seconds.
Strange that the rear courtesy lamps are not also illuminated. The footwell and rear courtesy lamps, and the inside rear view mirror lights are controlled by relay 42 in IP electrical center. All you need is a test light or DMM to troubleshoot.
I have not checked if the rears stay on, if they're on the same circuit I assume they would, but will confirm.
What is interesting, if the mirror is unplugged, the floor lamps go ff as they should after a few seconds.
I have not checked if the rears stay on, if they're on the same circuit I assume they would, but will confirm.
What is interesting, if the mirror is unplugged, the floor lamps go ff as they should after a few seconds.
Okay, just checked. Rear interior lamps stay on.
DIC and HVAC / radio go off.
Ok. So what else did you figure out based on the schematic provided?
Not too much to be honest.
I checked the pinout at the connector and all the voltages were correct, I only have a DMM so I can't analyze the singal lines.
Starting to wonder if maybe the BCM is sending a bad signal to light up all the lights. Although if that were the case, other lights would already be on.
Not too much to be honest.
I checked the pinout at the connector and all the voltages were correct, I only have a DMM so I can't analyze the singal lines.
Starting to wonder if maybe the BCM is sending a bad signal to light up all the lights. Although if that were the case, other lights would already be on.
I would be checking grounds ! The hatch and both doors provide a ground to the BCM. You will need to remove C2 to evaluate. A ground is provided on the appropriate pin when the hatch/lid/door is open.
Last edited by lucky131969; May 7, 2025 at 12:32 PM.
I would be checking grounds ! The hatch and both doors provide a ground to the BCM. You will need to remove C2 to evaluate. A ground is provided on the appropriate pin when the hatch/lid/door is open.
Okay I like your train of thought!
You mentioned "C2" I see it in the schematic in several places, where are you referring to?
Okay I like your train of thought!
You mentioned "C2" I see it in the schematic in several places, where are you referring to?
As in connector C2. On the schematic, you will see a dotted line between the wires. All wires captured in the dotted line are in one connector. The right of the wire designates the connector, the left of the wire designates the contact. If that does not make sense to you, I suggest you take your car to a trusted auto electric shop.
As in connector C2. On the schematic, you will see a dotted line between the wires. All wires captured in the dotted line are in one connector. The right of the wire designates the connector, the left of the wire designates the contact. If that does not make sense to you, I suggest you take your car to a trusted auto electric shop.
Thanks for the info, didn't how to read GMs schematic.
I'll pull off C2. I can verify different wires (LDoor, RDoor and hatch) going to ground but I would be surprised if these aren't working correctly.
When the mirror is unplugged, the lamps come and go of as they should with door / trunk opening
Well I pulled relay 42 which should turn off courtesy lamps and it does. But if I plug the mirror in, all the lights come on, even with the relay out of the car..
Well I pulled relay 42 which should turn off courtesy lamps and it does. But if I plug the mirror in, all the lights come on, even with the relay out of the car..
You have two switches on the mirror for the maps lights? If so, are they both switched the same direction ?
You have two switches on the mirror for the maps lights? If so, are they both switched the same direction ?
I have three buttons, its the automatic mirror - See pic below.
Pushing either of the lamp buttons does nothing. Pushing the "IO" button does toggle the green LED for auto dimming, not sure if it actually works since its hard to tell in the garage.
I did try pulling fuse #2 and #21 as mentioned in a different thread to check weather that would have an effect, it did not.
I have three buttons, its the automatic mirror - See pic below.
Pushing either of the lamp buttons does nothing. Pushing the "IO" button does toggle the green LED for auto dimming, not sure if it actually works since its hard to tell in the garage.
I did try pulling fuse #2 and #21 as mentioned in a different thread to check weather that would have an effect, it did not.
But did you have relay 42 pulled when you removed fuse #2 ?
Rearview mirror light stuck on
