HVAC control lights remain on
Thread Starter
Instructor
Joined: Dec 2005
Posts: 147
Likes: 3
From: Howell NJ
HVAC control lights remain on
I recently replaced the 14 lights in the HVAC control and discovered that if the car sits for a couple of days the battery is dead. The lights are never going out when the car is shut off. All other interior lights do go off.
According to the shop manual it looks like the BCM is responsible for this.
Could there be any other causes or a way to work around it without replacing the BCM?
According to the shop manual it looks like the BCM is responsible for this.
Could there be any other causes or a way to work around it without replacing the BCM?
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
My guess would be the HVAC controller is damaged or maybe you've got a solder bridge. Take it apart and look at your work again. The BCM might tell it to turn the lights on and off but it seems to do so over the data link so there must be some electronics inside the HVAC controller which actually control the lights.
Peter
Peter
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,170
From: Dyer, IN
I recently replaced the 14 lights in the HVAC control and discovered that if the car sits for a couple of days the battery is dead. The lights are never going out when the car is shut off. All other interior lights do go off.
According to the shop manual it looks like the BCM is responsible for this.
Could there be any other causes or a way to work around it without replacing the BCM?
According to the shop manual it looks like the BCM is responsible for this.
Could there be any other causes or a way to work around it without replacing the BCM?
Thread Starter
Instructor
Joined: Dec 2005
Posts: 147
Likes: 3
From: Howell NJ
When I put it back in (the firs time) there was a solder bridge which allowed the circuit board to do a good job of protecting the fuse. I cleaned the solder bridge and checked the rest of the bulbs, put a white wire in place of the missing circuit and all 14 lights are now on. I will pull it out again to see if I missed anything else that may have been fried. Is it possible to get a schematic of the board itself? The Helm manuals do not go into that kind of detail.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
All GM Circuit Boards are GM/DELPHI Proprotory. No schematics avaiable.
The module lighting IS controlled by the BCM. So,,,,,,,,,,if the light remain ON, the BCM is at fault.
Look at the yellow wire on C1 pin J OR C3 /B2, BCM connector. The Ground is G 202
BC
The module lighting IS controlled by the BCM. So,,,,,,,,,,if the light remain ON, the BCM is at fault.
Look at the yellow wire on C1 pin J OR C3 /B2, BCM connector. The Ground is G 202
BC
