I got a headlight problem too!
Thread Starter
Intermediate
Joined: Oct 2003
Posts: 31
Likes: 0
From: Glens Falls NY
I got a headlight problem too!
Hey guys just took the 99 vert for a cruise to the lake tonight and as it started to get dark I reached for the headlight switch and gave it a twist and... no lights!! I turn the switch on and off a number of times before they responded; what's up!! When I got back to My garage, I experenced the same condition a few more times. I hear no grinding or the motor running after the lights are turned on or off. The lights are on in the buckets, but just done want to pop up! Any ideas??
Drifting
Joined: May 2000
Posts: 1,917
Likes: 3
From: Southern NH
It sounds like the Headlight Control Module (HCM) located under the passenger headlight on the front of the wheel well. It's a small candybar-like box with 2 connectors coming out of it on either side.
If you look at the connector behind the headlights, it has 5 wires. 2 are for Headlight Open/Close, 1 is for Low Beam, 1 is for High Beam and 1 is Ground for Low/High.
The 2 Open/Close wires are Lt Blue/Dk Blue for the Passenger Side, and Lt Green/Dk Green for the Driver's side.
Take the Driver's side for example, both the Lt Green and Dark Green wires always have +12V in steady state. To Open the headlight, the Dk Green is momentarily grounded by the HCM. To Close the headlight, the Lt Green is momentarily grounded. It appears that the HCM is not doing that, either because it's faulty OR the connector could be having problems. The first thing to do is try to access the HCM and remove/reseat the connectors. You may be able to squeeze your hand under the passenger headlight when it's up but it's tight so the best way is to remove the access panel under the bumper and reach up.
If you look at the connector behind the headlights, it has 5 wires. 2 are for Headlight Open/Close, 1 is for Low Beam, 1 is for High Beam and 1 is Ground for Low/High.
The 2 Open/Close wires are Lt Blue/Dk Blue for the Passenger Side, and Lt Green/Dk Green for the Driver's side.
Take the Driver's side for example, both the Lt Green and Dark Green wires always have +12V in steady state. To Open the headlight, the Dk Green is momentarily grounded by the HCM. To Close the headlight, the Lt Green is momentarily grounded. It appears that the HCM is not doing that, either because it's faulty OR the connector could be having problems. The first thing to do is try to access the HCM and remove/reseat the connectors. You may be able to squeeze your hand under the passenger headlight when it's up but it's tight so the best way is to remove the access panel under the bumper and reach up.
Instructor
Joined: Nov 2003
Posts: 103
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From: lexington ma
Originally Posted by swimbob
Hey guys just took the 99 vert for a cruise to the lake tonight and as it started to get dark I reached for the headlight switch and gave it a twist and... no lights!! I turn the switch on and off a number of times before they responded; what's up!! When I got back to My garage, I experenced the same condition a few more times. I hear no grinding or the motor running after the lights are turned on or off. The lights are on in the buckets, but just done want to pop up! Any ideas??
