Headlight flashing between being "on" and "off" after a while
 

I have searched through the forums with no luck. After the headlights have been on for about 5 minutes they will start flashihg between being "on" andthe daytime driving lights. Tail lights never go off or flicker, just the headlights. I would hear a buzz from the relay's in the dash but have rotated them (since they are the same) and no change. I am usually pretty good at diagnosing but this is throwing me for a loop. Could it be the on/off switch?

RE: Headlight flashing between being "on" and "off" after a while
 

The headlight relay should be under the hood...

Though, not sure on what year we're dealing with...

RE: Headlight flashing between being "on" and "off" after a while
 

Thanks for the response, it is a 1996 Blazer. The buzz comes from the glovebox relay bay, there is one under the dash that I can check?

RE: Headlight flashing between being "on" and "off" after a while
 

There should be one in the under hood fuse box...

RE: Headlight flashing between being "on" and "off" after a while
 

I will check and replace to see if it resolves the issue. BTW, Happy Thanksgiving!

RE: Headlight flashing between being "on" and "off" after a while
 

should be able to just swap it with one of the other relays in there as a test...

And thanks! even though mine was last month ;)

RE: Headlight flashing between being "on" and "off" after a while
 

Yep , the A/C and Headlight relays are exactly the same so you could swap them and see if the problem goes away , if that doesn't fix it , it's something else ...

RE: Headlight flashing between being "on" and "off" after a while
 

Well a new problem popped up and my rear window won't open , door locks don't work and the power mirrors are dead so I took it in and it is the BCM ( Body Control Module ) that needs to be replaced ...
I was quoted with just a quick price of around $800 to $1000 by GM as I won't get it fixed until after Xmas ..
As soon as it first started acting up that's what I thought it was and my warranty just ran out in September [:@]

Zed

RE: Headlight flashing between being "on" and "off" after a while
 

That bites... It sucks because that's a dealership only fix... The BCM has to be programmed specifically for your truck.


Maybe you should see how much extended warranty is going to cost for like a year, and if it's cheaper, go for that, lol.

RE: Headlight flashing between being "on" and "off" after a while
 

Hmmm , never even thought about another extended warranty , the last one was ( I think $400 ) for 4 more years ..
I wonder if I could pull that off ??

Thanks !

Zed