Weird problem! Input please?

[Ltl_red]

My 1996 S-10 Blazer (4.3L 4X4) has a problem and I would like to know if someone else has heard of this, and what the problem may be.

It acts like a highway patrol vehicle (really), I mean the headlight flash on and off on their own and just go nuts. This only happens when the "night" headlights are on and it does not affect my daytime running lights. I was only happening a few times, but now once the lights are on for about 3 minutes they will go into highway patrol mode. Also when they flash I can hear a clicking noise on the passenger side (dash area)Now the cool thing about it is that people actually get out of my way, but on a pitch black night wow look out, and not to mention if a real Cop saw me like that = "Ticket".

So if anyone has any idea what could be wrong I would appreciate the input.

[wolfox]

Probe headlamp sockets/wireharnesses to find any shorts/partial shorts to ground and also make sure that you have the correct headlamps installed. Going up in wattage will do this as it makes the circuit think it's overloaded and activates a thermal breaker. Also make sure that there are no shorts to ground in your trailer wire harness and your rear lights. Chasing this one's going to be difficult, but working methodcally with a voltmeter will reveal if there are shorts or partial shorts to ground that could be overloading and forcing the thermal breaker in the headlight switch itself to open to cool, then once cool, closing the circuit again. This is why you'e flashing like a mad HiPO. If worse comes to worst and neither you or a shop can find the short, blame the headlamp switch. I have read of one or two instances where this was the case and replacing it took care of it, but ONLY *after* eliminating the possibility of shorts in any of the body wiring. Good luck, electrical problems are a bear to get under control.

[BlazerLT]

A wire/connection is loose or the headlight relay needs to be replaced.

[Jeremy Fitch]

I would have a check of the headlight relay as well. Isn't it behind the glove box?

[mike2004tct]

Originally Posted by Jeremy Fitch

I would have a check of the headlight relay as well. Isn't it behind the glove box?

Yes, behind a cover in the glove box that has "Relays" printed on it.

[JA no Y]

Are you sure your balzer wasn't possesed by the ghost of a dead highway patrol vehicle?

[Ltl_red]

I think it may have been possessed. I have the weirdest things happen with my truck. The last problem I had no one even had a clue as to what it was, at least this one you all had some ideas as to where to look. I thank you all for your input, I will try the relay first before having to tackle the "Electrical" headache.

[BlazerLT]

Yea, it sounds like the relay is taking a crap when you hear it clicking like that.

[rasmith527]

Sounds like your highbeam switch needs to be replaced, or something along that line. Since the daytime running lights use the highbeam circuit, they may not indicate any trouble (not to mention it is hard to tell during the day anyway). Does your lights flickering affect anything else in or on your Blazer?

[blazer_guy86]

I had a buddy with a 94 s10 that had the same problem. But it was because we had wired some fog lights powered by the low beams.

Low beams would be on a couple minutes and they would start to flashing. Turn on the high beams and they stopped flashing. This happened because of an overload. This might be your problem(that there is an overload or a short) but could also be a relay.

[Ltl_red]

Originally Posted by rasmith527

Sounds like your highbeam switch needs to be replaced, or something along that line. Since the daytime running lights use the highbeam circuit, they may not indicate any trouble (not to mention it is hard to tell during the day anyway). Does your lights flickering affect anything else in or on your Blazer?

The only thing affected is my dash lights, which are in working order with my possessed lights. Otherwise nothing else.
I still have not had a chance to check the relay so can not reply yet as to if that was it or not.

[Ltl_red]

Thank you everyone for your help. I found the problem and it was an easy fix. It turned out to be the actual headlight switch. If anyone else runs into this problem, it just takes 5 minutes and $23.00 to replace. Unscrew the phillips screws above the RPM gage, and the whole thing pops out, then unsnap the headlight switch, replace and screw back into place.
Again THANK YOU ALL!!

[BlazerBoyLT98]

Originally Posted by Ltl_red

Thank you everyone for your help. I found the problem and it was an easy fix. It turned out to be the actual headlight switch. If anyone else runs into this problem, it just takes 5 minutes and $23.00 to replace. Unscrew the phillips screws above the RPM gage, and the whole thing pops out, then unsnap the headlight switch, replace and screw back into place.
Again THANK YOU ALL!!

Great to know that was the fix. I had the same issue happen on a Ford Thunder Chicken I owned, however I sank the chicken before I could fix it!

[wolfox]

Wow, I feel smart, I was right! Glad to know you got it fixed man. Same thing happened on a buddy of mine's Blazer here in town. $20 later we had a new light switch in the box, haf an hour later, steady driving lights. Good work!

Originally Posted by Ltl_red

Thank you everyone for your help. I found the problem and it was an easy fix. It turned out to be the actual headlight switch. If anyone else runs into this problem, it just takes 5 minutes and $23.00 to replace. Unscrew the phillips screws above the RPM gage, and the whole thing pops out, then unsnap the headlight switch, replace and screw back into place.
Again THANK YOU ALL!!

[97BlazerLT]

OK - Hear is the Deal... I have a 97 Blazer LT and My High beams work great but i have no Low beams. the bulbs are good. I belive it is the relay that is in the glovebox but which one is it?? There are 3 of them in there. Can anyone tell me what relay goes to what.... The Switch on the is good cause i can switch between the 2 but there is no headlights that come on when i switch it to the lows.