headlight trouble!!??

[ChevyToy04]

I bought a 1990 fullsize blazer Monday. Last night while driving to the shed, I noticed that the drivers side headlight quit working. A few seconds later passenger side went out. Almost like a fuse blew. High beams still work fine but no low beams. I beat on the dash and the dah lights starting working. Where is a good place to start checking for the problem with lowbeams?

 

[ChevyToy04]

I did a search and only found one thread that had the same problem as me but no answer to how to fix it. Tried to pm the guy but his box was full or something

 

[Fordum]

Well, the high and low beams use the same grounds, so a bad ground should kill both.
Were they really bright before they went out? I wondering if your voltage regulator is bad and blowing the bulbs with high voltage.

The first thing to check is the bulbs. Always check the obvious stuff first.

If they are good, then the wiring between them might be suspect.
The highbeam switch switches between two common wires. One for high, and one for low, so if it were bad, then both low beams should have gone out together.

 

[ChevyToy04]

I don't have dual headlights whether that matters or not. The lights were working normal. I turned them off, and came back pulled the knob to turn them on and lost the drivers side. Drove towards the shed and lost the other. Something to do with the switch possibly?

 

[Fordum]

I don't have dual headlights whether that matters or not. The lights were working normal. I turned them off, and came back pulled the knob to turn them on and lost the drivers side. Drove towards the shed and lost the other. Something to do with the switch possibly?

Figured you did, but it should not make a difference.
It still sounds like either bulbs, or front end wiring. Neither the headlight switch or the high beam switch differentiate between the left and right.

They just use the one wire out to the front fenders where it splits to the two bulbs.
Check the bulbs and if they are blown check the voltage.

And if both bulbs are blown with correct voltage, don't buy any lottery tickets anytime soon.
You must be going through a bad luck streak for both bulbs to go out that close to each other............

 

[ChevyToy04]

When I get home from work and college I will take a look at it if I have time. I will pick up some bulbs before i go home just in case. I will let you know what I come up with. Preciate your help so far!

 

[4X4HIGH]

Check ALL electrical grounds, 99% of electrical trouble turns out to be a bad ground somewhere.

 

[ChevyToy04]

Thank god it was simply the bulbs were just blown! Preciate all the help everyone

 

[Fordum]

If they keep blowing, be sure to check the voltage.

 

[ChevyToy04]

Will do. I've turned them off and on and so far they're working fine

 

[496truck]

Old bulb filaments. Just enough shock can separate them. Can't tell you how many times we replace a bulb on one side of a car, shut the hood or trunk, and the same bulb on the other side goes out. Or soon thereafter. Send out the customer with a new h/l bulb, they come back same day, next day, couple days, "My light is out again. What did you guys do?!!" "No, ma'am. We replaced the other side. Now this one is out."

It happens...