Is there a know all tell all article for how to troublesheet the headlight system on a 2004 Blazer? I am a total newb when it comes to troubleshooting anything electrical on modern cars... I had a handle on things when everything was analog, but digital confuses me... I can't ever figure out how to use my new multi-meter and todays instruction manuals for one do not help at all...

 

Never mind, the previous owner put the relay in upside down.... At least some of my experience came in handy

 

nice catch.

George

 

I feel sheepish now, it wasn't till I realised that the relay only had four pins that I thought to try flipping the relay.... I thought all automotive relays still had 5 pins... Thats what I get for thinking

 

Good catch. Thanks for following up to let us know the resolution to your question. It's definitely a good reminder that sometimes the solution is quite simple and easy to overlook.

 

If I remember correctly, the 4-pin relays are configured so that you can put them in both ways, i.e., the leads for the switch are in opposite diagonal corners with the coil leads in the other ones.

Of course this assumes there are no diodes in your relay so that polarity matters.

I discovered this when I was diagnosing what turned out to be a bad starter relay. I was confused as to why the relays could be put in both ways. I then discovered the pin configuration allowed for this.

So, did you by chance swap relays of the same type? And could that be the reason your issue was resolved?

 

From christine_208 "So, did you by chance swap relays of the same type? And could that be the reason your issue was resolved?"

I did not, I just pulled it out noticed the four prongs and turned it over and it worked...