vmax84

1989 4Runner with 22re.

Low beams work fine for 10 or 15 minutes, then they'll just quit. Flip the high beams on and the high beams come on just fine (and the high beam indicator comes on as it should). Flip the switch back to low beams and the high beam indicator stays on and the low beams still don't come on.

Clues? Thanks.

vmax84

mt_goat

Do yourself a favor and buy 4crawler's headlight wiring harness upgrade.

http://www.4crawler.com/4x4/CheapTri...OnLineOrdering

gte718p

Sounds like you have ground issues. I don't really think 4crawlers harness is going to help. I also end to think its overrated. I run 100W Hella H4 with no problem.

First set is always, have you check all your fuses, and have you tried a different set of bulbs?

myyota

It sounds like you have a bad headlight switch.

HAVOC

At the top of that page from 4crawler shows how to repair your headlamp switch. It might not fix your problem, but something to look at.

mt_goat

So let me get this straight, you think its a grounding issue but you don't think a new wiring harness with a NEW ground wire is going to help any. And you think it may be a fuse???

mt_goat

Yeah this I agree with, those switches can get carbon buildup on them. The nice thing about Roger's harness upgrade is it takes the high amp load off the switch (which causes the carbon buildup in the first place) and puts it on the relays in the upgraded harness.

gte718p

Actually no. Because the 4crawler system uses the entire wiring from the old system to activate relays. A ground or lack there of on the control side will still be ground in the control side with a new add on harness. I'm not saying its not a good system. I'm going to use it on my crawler to when I run 4 120w bulbs. That is well more the the stock wiring can handle.
And yes a fuse could cause it. When fuses blow electricity finds strange paths. Especially in older vehicles with potentially compromised wire. You don't even begin to want to know the problems I had restoring my corvette. Incredibly strange things happened when I blew a fuse.

I'm leaning toward on of the grounding straps is broken. What do I know I only consult for people designing electric an hybrid vehicles.

mt_goat

Well it takes very little power to activate a relay so it just makes sense on an old truck with a possible weak ground to take the load off the old system and put it on a new upgraded system.

If he had a blown fuse I don't see how the highbeams would work. But what do I know, I'm just a mechanical engineer.