headlight module

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Apr 5, 2015 | 01:38 PM

c5yeti

Thread Starter

3rd Gear

Joined: Apr 2015

Posts: 3

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headlight module

my head lights stopped going up or down a few months ago. I finally got tired of manually cranking them up and down so I started the diagnostic process. I have done a lot of research on the pop up headlights trying to diagnose if my module or headlight switch has gone bad on my car. I cant find a decent wiring schematic that gives pin-outs for the C1 connector that connects to the module. with headlights on, pin C on the C1 connector goes to open, is this correct? I would assume it should switch to ground. A and C reversing to tell module to lower the lights?
Pin A and C are not shown on the wiring diagram I am finding.

C1 headlights off
A - ground
B - Power
C - Power
D - Ground
E - Power

C1 headlights off
A - power
B - Power
C - open (nothing)
D - Ground
E - Power

Apr 6, 2015 | 11:52 AM

dadaroo

Le Mans Master

Joined: Mar 2011

Posts: 6,835

Likes: 301

From: Columbia SC

Not at home with my schematics.

I assume your second set of readings is with headlights ON, not OFF?

Also, are your readings with the connector still connected to the module?

If you have Twilight Sentinel and activate it from the DIC do they work in the dark?

You can cover the light sensor at the left side of the drivers side defroster vent to test in the daylight.

Apr 6, 2015 | 12:35 PM

c5yeti

Thread Starter

3rd Gear

Joined: Apr 2015

Posts: 3

Likes: 0

The second set would be ON and connector unplugged. The car does not have twilight.

Apr 6, 2015 | 07:18 PM

Chicago1

Race Director

Joined: Mar 2008

Posts: 12,413

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From: Rio Rancho NM

hope this helps...it's free to do so you can eliminate the issue. You sure it's not the nylon gear that took a crap?

https://www.corvetteforum.com/forums...f-replace.html

Apr 7, 2015 | 09:40 AM

dadaroo

Le Mans Master

Joined: Mar 2011

Posts: 6,835

Likes: 301

From: Columbia SC

Everything going into the module checks out OK. There are 2 schematics for the door controls. Here is the info.

C1 headlights off
A - ground (this is the On input and is correct)
B - Power (always Hot)
C - Power (this is the OFF input and is correct)
D - Ground (always ground)
E - Power (always Hot)

C1 headlights ON
A - power (this is the On input and is correct)
B - Power (always Hot)
C - open (nothing) (this is the OFF input and is correct)
D - Ground (always ground)
E - Power (always Hot)

Hope this helps.

Apr 7, 2015 | 10:08 AM

c5yeti

Thread Starter

3rd Gear

Joined: Apr 2015

Posts: 3

Likes: 0

That helped a lot! I will turn my attention to the module. The motors are good I can have them go up and down using my power probe.

Apr 7, 2015 | 11:49 AM

dadaroo

Le Mans Master

Joined: Mar 2011

Posts: 6,835

Likes: 301

From: Columbia SC

PS: I meant to mention I would have expected in "OFF" the A pin to be open and not ground. Kind of what happens in "ON". With that said there are some lighting circuits upstream of that circuit that could account tor a resistance reading but not ground.

I think if they will not go up that there is NOT an issue with anything "up to" the module.

If you are not using an ohmmeter to measure the circuit that might account for what you got.

If I need to check the same with my car I can do it in the next day or two. It is at my warehouse and not at home.