Courtesy Light Nightmare
Thread Starter
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
Courtesy Light Nightmare
Guys help me out here.
1985 Corvette,
Interior lights stay on all the time.
From my research I found that its either the door switches, or the timer/dimmer module.
I read that I would be able to bypass the module and only lose the timer function, which I am an entirely OK with, so I did just that.
The lights still stay on all the time.
I replaced both door switches, and disconnected my hatch switch with both doors closed, lights still on.
Do I have a short to ground somewhere?
From my understanding the white wire is always hot from the CTSY fuse, and the switches ground when the doors are open, completing the circuit and lighting the car up.
So by bypassing the module, All I would need to turn the lights on is a ground. If my switches are new, and the hatch is disconnected, I must have an open ground somewhere?
Thanks for any input!!
Jeremy
1985 Corvette,
Interior lights stay on all the time.
From my research I found that its either the door switches, or the timer/dimmer module.
I read that I would be able to bypass the module and only lose the timer function, which I am an entirely OK with, so I did just that.
The lights still stay on all the time.
I replaced both door switches, and disconnected my hatch switch with both doors closed, lights still on.
Do I have a short to ground somewhere?
From my understanding the white wire is always hot from the CTSY fuse, and the switches ground when the doors are open, completing the circuit and lighting the car up.
So by bypassing the module, All I would need to turn the lights on is a ground. If my switches are new, and the hatch is disconnected, I must have an open ground somewhere?
Thanks for any input!!
Jeremy
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
I read that I would be able to bypass the module and only lose the timer function, which I am an entirely OK with, so I did just that.
HOW DID YOU ATTEMPT TO DO THIS?
From my understanding the white wire is always hot from the CTSY fuse, and the switches ground when the doors are open, completing the circuit and lighting the car up.
THIS IS INCORRECT - PINK/BLK or ORANGE IS A CONSTANT POWER TO THE LAMPS, THE WHITE WIRES GO TO THE CONTROL DEVICE (in this case the dimmer module), which passes it on to the DOOR SWICHES
Jeremy
HOW DID YOU ATTEMPT TO DO THIS?
From my understanding the white wire is always hot from the CTSY fuse, and the switches ground when the doors are open, completing the circuit and lighting the car up.
THIS IS INCORRECT - PINK/BLK or ORANGE IS A CONSTANT POWER TO THE LAMPS, THE WHITE WIRES GO TO THE CONTROL DEVICE (in this case the dimmer module), which passes it on to the DOOR SWICHES
Jeremy
If you have a FSM look in the vicinity of 8A-114 maybe for the INTERIOR LAMP functions. I don't have but it should be similar ALL YEARS.
I believe I can supply a diagram if needed that should be correct.
Last edited by WVZR-1; Aug 12, 2015 at 07:17 PM.
Team Owner
Joined: Jan 2003
Posts: 20,322
Likes: 248
From: Summerland B.C. Canada
From my understanding the white wire is always hot from the CTSY fuse, and the switches ground when the doors are open, completing the circuit and lighting the car up.
So by bypassing the module, All I would need to turn the lights on is a ground. If my switches are new, and the hatch is disconnected, I must have an open ground somewhere?
Thanks for any input!!
Jeremy
From my 86 service manual
http://members.shaw.ca/dankai/Interior%20Lights.pdf
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
The light switch rod? I try to give ALL the benefit of doubt.
The FSM excerpt you posted is the same as what he should find in his FSM when he looks. The location in ALL FSM's should be indexed similarly.
Last edited by WVZR-1; Aug 13, 2015 at 10:35 AM.
Thread Starter
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
Thanks for the help guys, gonna tackle this today after I finish doing brakes on my Gma's Buick.
It is in my FSM, in the "manual supplement" Should have looked there!
And no...my headlight switch isn't in the "courtesy light on position" LOL
It is in my FSM, in the "manual supplement" Should have looked there!
And no...my headlight switch isn't in the "courtesy light on position" LOL
Thread Starter
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
Just went out and bypassed the module, the white wires are jumpered together and now my lights go on and off with the doors opening/closing. This can be done without any cutting of the harness, just take a jumper wire from white-white. I used two "open barrel crimp" connections, both male. They are in there pretty snug.
Not sure why on the other website I read it told me to take the black wire to the white wire....White to white is the correct way to do it.
Thanks guys!!!
Jeremy
Not sure why on the other website I read it told me to take the black wire to the white wire....White to white is the correct way to do it.
Thanks guys!!!
Jeremy
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Pro
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There was a TSB on bad door switches which corroded, they improved the door switch design in later years.
The hatch switch has a plastic rod with a tab that breaks leaving the rear ctsy lights on in cargo area, found this out when my lights stayed on one night.
Use a test light to check for shorts to ground, this is the easiest way to find which wire has the short.
The hatch switch has a plastic rod with a tab that breaks leaving the rear ctsy lights on in cargo area, found this out when my lights stayed on one night.
Use a test light to check for shorts to ground, this is the easiest way to find which wire has the short.
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
7th Gear
Joined: Aug 2008
Posts: 7
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Just went out and bypassed the module, the white wires are jumpered together and now my lights go on and off with the doors opening/closing. This can be done without any cutting of the harness, just take a jumper wire from white-white. I used two "open barrel crimp" connections, both male. They are in there pretty snug.
Not sure why on the other website I read it told me to take the black wire to the white wire....White to white is the correct way to do it.
Thanks guys!!!
Jeremy
Not sure why on the other website I read it told me to take the black wire to the white wire....White to white is the correct way to do it.
Thanks guys!!!
Jeremy
thanks...... or if you can give me some more info about where and how... will be great... thanks for your time
Safety Car
Joined: Aug 2009
Posts: 3,752
Likes: 276
From: Melbourne, Victoria, Australia
Hi
Have you tried to replace the board ? they are quite cheap.
I have had to replace my courtesy delay timer a couple of times in the 20+ years I have had my 85, they just fail at any time like a light bulb.
sometimes the lights don't work other times they stay on.
Anyway the shop manual is a must when you have a C4, the diagnostics and wiring diagrams are very helpful.
http://www.parts123.com/corvettecent...50f&ukey=29596
Have you tried to replace the board ? they are quite cheap.
I have had to replace my courtesy delay timer a couple of times in the 20+ years I have had my 85, they just fail at any time like a light bulb.
sometimes the lights don't work other times they stay on.
Anyway the shop manual is a must when you have a C4, the diagnostics and wiring diagrams are very helpful.
http://www.parts123.com/corvettecent...50f&ukey=29596