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I have a 99 C5. The device in the photo is located just behind the driver side head light. It has started ticking. I am sure it should not do this. I have also had issues with the driver side headlight. Are these related? If this is a relay, what are the symptoms of this device going bad?
That is the headlamp door control module. I have read that they are a relatively common failure item. Never had to replace one so that's about all I have. Others can probably fill in the details.
That is the headlamp door control module. I have read that they are a relatively common failure item. Never had to replace one so that's about all I have. Others can probably fill in the details.
Thanks. I figured it has something to do with the headlight system. This one has started ticking. It does this even when the car is setting parked. This one is on the passenger side (not the driver side as I may have referenced).
I have had issues with the passenger side HID bulbs glowing out a lot. And recently, the lights won,t do down unless i flick the high beams on and off.
Might that be related to the control module?
Are there one module for each light?
Was the headlight control module on the "drivers side" of the car on the earlier year cars?
First post above states the device in question is on the "drivers side".
For the later year cars the headlight control module is definitely on the passenger side.
Yes, I was attempting to clarify my initial post. The module is on the passenger side, just behind the headlight assembly. It is ticking all the time. I am afraid it may be pulling current from the battery. Is the ticking an indication of an issue with the module?
Last edited by gpruitt54; Sep 26, 2016 at 01:40 PM.
Electrical schematics make me cross-eyed, I never learned how to read them. I appreciate you including it in your reply. I will try to make since out of it.
Electrical schematics make me cross-eyed, I never learned how to read them. I appreciate you including it in your reply. I will try to make since out of it.
You might want to pull the two fuses shown in the first schematic so you don't kill the battery.
With the module on my car making ticking sounds along with the occurrence of my headlights going up and not going down (except when I cycle the high beams), does a clicking module mean it is bad and needs to be replaced?
I don't understand electrical schematics enough to know what fuses (if any) are referenced.
OK. Time for your first lesson.
Look at the very top of the first schematiic
The Underhood Electrical Center is the fuse box in the engine compartment.
Anything shown inside the dotted line is found in that fuse box. Minifuse 3, is power for the right hand headlamp door circuit.
Minifuse 4 is for the left hand headlamp door circuit.
Inside the fuse block cover will be printed the locations of all the fuses and relays in that fuse block. The backward "S" labeled B and A is how a fuse is represented in a wiring schematic. When you find what you think is the correct fuse, you should be able to verify that by the fact that they are 10 amp (10 A) also shown inside the dotted line. There are probably many other 10 A fuses in there but just in case you get 1 row off and it's a 15A fuse you need to take another look.
Yes you probably need a new module. Without doing the electrical checks it is not possible to know for sure. I think parts recycler Vettenuts here on this forum would be a good place to check if you want used.
OK. Time for your first lesson.
Look at the very top of the first schematiic
The Underhood Electrical Center is the fuse box in the engine compartment.
Anything shown inside the dotted line is found in that fuse box. Minifuse 3, is power for the right hand headlamp door circuit.
Minifuse 4 is for the left hand headlamp door circuit.
Inside the fuse block cover will be printed the locations of all the fuses and relays in that fuse block. The backward "S" labeled B and A is how a fuse is represented in a wiring schematic. When you find what you think is the correct fuse, you should be able to verify that by the fact that they are 10 amp (10 A) also shown inside the dotted line. There are probably many other 10 A fuses in there but just in case you get 1 row off and it's a 15A fuse you need to take another look.
Yes you probably need a new module. Without doing the electrical checks it is not possible to know for sure. I think parts recycler Vettenuts here on this forum would be a good place to check if you want used.
Got it. Yes, both fuses are good and have not blown. At the moment, the module is not clicking and does not feel warm. When it was click, I do not recall any temperature differences. I will nave to watch for that.
Did you check the headlight module by touching it to see if it is warm?
If it is warm then the module is likely bad because warm would mean that it is drawing current in the headlight motor circuit. The module should only draw current when the headlight motors are running and NOT at all times. So normally the module will not feel warm.
The removal of fuses 3 and 4 in the under hood fuse box will stop the motor from being able to draw current. But it also means that the headlight switch inside the car will NOT be able to raise the headlights. So when you want the headlights raised you have to manually raise them with the reverse of what you now do to lower them.
The headlight switch in the car WILL continue to be able to cause the lights to be illuminated because there are other fuses for the LIGHTS. Fuses 8 and 9 in the under hood fuse box are for the right (passenger) side low beam and high beam and fuses 10 and 12 for the left (driver) side low and high beam.
If you have an owners manual there are fuse box layouts in the back of the manual that you can look at to see where the fuses are located. There should also be a diagram inside the cover for the fuse box if you do not have the owners manual.
Yes, I have the manual and I have located the associated fuses.
Got it. Yes, both fuses are good and have not blown. At the moment, the module is not clicking and does not feel warm. When it was click, I do not recall any temperature differences. I will nave to watch for that.
The clicking sound you were hearing was the mechanical relay inside the door control module turning on and off. That isn't normal.
I can't say what problems can come up when using aftermarket HID headlights. I've never used them.
Here are a couple things that you can check.
When working on the electrical system it is a good idea to disconnect the negative battery lead.
Unplug the connectors from the door control module and and inspect the connectors for any corroded or bent pins.
Unbolt the module from the car and check to see that the case is intact and no water can get in. Refer to the link in my earlier post.
Locate Splice Pack 100 (SP100) and Ground 102 (G102) Take the splice pack apart and check for corrosion .
Check that the ground to the frame is clean and tight.
I have my doubts that those things will be the problem but at least you can eliminate them as the cause of the problem.
Ticking device, should it do that?
