High beams wont work. 9 out of 10 times...

Kolk1

New member
Nothing has changed in my settings, I dont use auto off high beams, havent replaced the battery, had this car over 4 years now, and over 100k miles now as well.

If I sit there and flash my high beams, they will only come on maybe once or twice out of 10 flashes. It happens to both lights, so its not just one is sticking. Dash says they are on(but they arent). I drove for awhile with them ON (but off) and they came back on a couple minutes later.

I havent dug into the car yet, but it obviously cant be a fuse or it would never work. Unless a relay is starting to fail to cause it to work intermittently, but that seems unlikely.

I do vehicle electronics for a living, but im just curious if anybody has seen this before, and what their solution was, before I dig in to it. Thanks.
 
Any other issues?  I would suspect the multifunction switch first, myself, then possibly the highbeam control module for the auto highbeams.  Each HID headlamp has its' own solenoid.
 
I had similar issue long ago where high beams would not work. Same symptoms. I did have the auto high beams set to on. What corrected my problem was to cycle through the settings. Turning the auto high beams on, then off, then on again fixed it for me. I left the auto high beams on. Also, I don't remember if when I cycled them off if I started car or not. I think I did but not sure.
 
No other issues with the car. I just did a basic look over, nothing obvious, and auto high beams still off. I'll try to cycle it and see what happens.

Dash shows the high beams are on, so the switch is sending a signal at least that far lol
 
Ok so I did a little digging, was looking for anything loose, checking relays and so on. I can hear a delay clicking under the dash as part of the cabin fuse box, so I figure I'll start looking for its output to see if it's working, this whole time my car is engine off, ign on so I can try and flash my lights, sooo guess what, my battery goes dead. So I turn everything off, put the car on a charger, wait about 1/2 hour and the car starts right up like always, but now ever single time the high beams have worked. I've flashed them or used them about 30 times now without a single issue. And before I could only get them to work about 1 out of 10. So who knows. lol
 
The high beams have been an issue now for a couple weeks now at least. The battery was fine until I was flashing the lights with the engine off for about an hour. Its just over 100 miles round trip for me to go to work every day, this may have been going on for awhile, but i honestly just started using my brights a lot recently since this summer I moved out to the stick, and now its dark on my way home from work. I replaced the batter with a 850cca less than 2 years ago. Also, while driving you obviously dont use the battery, you are using the alternator for everything. So I doubt it had anything to do with the battery, BUT killing the battery would be the same as disconnecting it and letting any ECU or BCM do a reset.
 
Well, if a reset of the PCM was happening "automatically", you'd know because the driving feel would change.  Don't know if the battery would have to be completely dead (no voltage) for this to happen (with engine off), or if it can happen simply dropping below 12V (or some other threshhold).
 
Any luck with this?  I'm experiencing the same thing with my 2011.  It happened when I was testing while testing the headlight I was swapping in and now both won't work.  I think there maybe a safety built in somewhere that disables them if a failure is detected.

SHOdded said:
Well, if a reset of the PCM was happening "automatically", you'd know because the driving feel would change.  Don't know if the battery would have to be completely dead (no voltage) for this to happen (with engine off), or if it can happen simply dropping below 12V (or some other threshhold).
 
Back
Top