Headlight switch?

Last night the lights started acting up. They won't come on in the auto position. They work in the headlight position on both high and low beam, but the high beam indicator doesn't come on in the cluster. I can flash high beams in the auto position but they don't remain on. The needles for tach and speedo also do not light up but the gauges appear to be working.
I removed the DRL relay and the symptoms remain so I reinstalled it. I haven't had time to check it with my scan tool to see if any BCM issues show up.
Headlight switch is simple enough to replace so I just ordered a new one. Has anyone else seen an issue similar to this?
This is for a 2006 with 151k miles.
 
depending on symptoms there is also a known issue with a DRL resistor
http://ricksfreeautorepairadvice.com/drl-indicator-flashes-b2600/
With the age & miles I'm tempted to get one anyway as a preventative if it's not already bad.
This morning when I started the vehicle, I had parking lamps only with light switch on auto. In the headlight position I had both high & low beam but no high beam indicator on the cluster. The gauge needles were also dark. Upon backing out of the garage I noticed that the gauges were suddenly lit up normally with the exception of the odometer. It functions but the LED numbers don't light.
 
DRL resistor replaced. Headlight switch replaced. No luck. It's somehow tied into the fog lights. Almost like something is backfeeding power to the fog light switch because sometimes the LED indicator is on full, sometimes on dimly but the switch won't turn the fog lights on most of the time. I've replaced that switch also.
Unplugging the fog light switch makes it so that the gauge needle lights will not come one. Neither will the blue high beam indicator, but the high beams work. Plug the switch back in and I have the gauge needles as soon as I step on the brake and put the car into gear. Very perplexing.
 

melsg5

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you mentioned a BCM scan did you do that?
you mentioned the lights were effected by the ambient light sensor when you backed out of the garage, could there be an issue with that?
are you working with any kind of wiring diagram to see how the circuits are related?
 
you mentioned a BCM scan did you do that?
you mentioned the lights were effected by the ambient light sensor when you backed out of the garage, could there be an issue with that?
are you working with any kind of wiring diagram to see how the circuits are related?
I've got 3 scanners. One is a generic thing that does a few things a GM ScanTool 2 does. I've programmed fobs with it. Now it appears that if I plug that one in in try anything, the Brake and ABS lights come on when I step on the brake after removing the scanner. Unhook the battery to reset and those lights remain out.
An iPhone app called BlueDriver with it's own module does not make the Brake & ABS lights come on but it's basically limited to reading and clearing codes and suggesting common fixes to codes.
I'm now getting a MIL circuit code, P0650. The MIL will light up for a fraction of a second when turning the key on so I don't think the bulb is dead.
I'd like to pop the plugs off of the ECM and hit them with some electrical parts cleaner but I can't seem to figure out just how to unplug them.
One thing seems to lead to another here lately.
 
OK, this will get me dumbass of the day award. Well deserved but I'll suffer it in hopes that it may help someone else avoid the situation.
I added a second 12V plug so that a heated seat pad and dash cam would shut down when the key was turned off, as the lone factory plug is always hot.
I used a piggy back tap to add a fuse to power the new 12V outlet. There are slots for 2 fuses in it, 1 for the new application and another for the original circuit in the fuse block.
I neglected to insert a fuse for the original use once I'd gotten the new 12V plug operating. Put the second fuse in today and all is well again.
The circuit in use is the IGN in the very top right corner of the console fuse block in the interior of the vehicle. I really feel foolish, but I also feel better that it was this and not some hard to trace fault somewhere else along the line.
All light functions (auto, DRL, cluster needles, etc) are back to normal. The only exception seems to be the digital odometer. It's functioning but doesn't light up at all. Is it just backlight by a bulb of some sort? A twist lock LED? What size?
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great that you found out the problem but how long ago did you add that piggy back tap?
Pretty recently. Never occurred to me that it could be the problem. I'd never really used one for anything else and wasn't that familiar with how they operate.
On a related note, I pulled the dash trim from around the cluster as I was going to check the back of the cluster to see if there were replaceable bulbs causing the dark odometer. It lit up as soon as I yanked the dash trim off. Popped it back together. It remains working at this time. I'll take that dumb luck all day.
 
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