The hazard lights, signal lights and high beams are not working, what could be the cause of these problems?

SAPPHIREROSE

MEMBER
2006 BUICK LUCERNE
3.8L
V6
2WD
AUTOMATIC
220,000 MILES

I have the car listed above CXL. Currently my hazard lights, signal lights, bright lights will not work. The blue light for high beams will not display on the dash and neither will the green turn signal arrows and they don't work outside the car either. I've checked all of the relays and fuses that I can think of, and I've also replaced the multifunction switch and I'm still having this issue. I took it to an auto shop, and they could not pull any codes from it. Also hood open keeps displaying across my Dash and my hood is definitely closed. Any ideas?

Sunday, August 21st, 2022 AT 8:23 AM

1 Reply

JACOBANDNICKOLAS

MECHANIC
110,114 POSTS

Hi,

I attached a couple of pictures below. What I need you to do first is to check if there is power to the fuses 10 and 11 in the under-hood fuse box. Pic 1 below shows the fuses. Check these when the high beam is requested.

It's likely that you checked the fuses, but we need to check for power.

Here is a link that you may find helpful:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

If there is no power, my first suspect is the printed circuit board (PCB) has failed. It gets power directly from the battery and is not repairable. Pic 2 shows the PCB relays. Note that the affected components are part of the PCB. There are other PCB relays in the same box that run other things and are working. So, this really is my first suspect.,

The remaining pics are testing procedures for the PCB.

Let me know what you find or if you have other questions. Additionally, let me know if this happened at the same time.

Take care,

Joe

See pics below.

Images (Click to make bigger)