Weird headlight problem

[Poppadiesel]

This winter while shovelling snow, I noticed that the headlights of my 97 4Runner (4 cylinder) were on. I thought I must have left the headlight switch on, but a quick check showed that it was in the off position. A little later while driving, I noticed that the signal light flasher began to buzz and could only be quieted by putting on either left or right signal lights. None of these symptoms occurred when I took it to our local Toyota dealer, of course. They suggested I remove the steering column covers to get at the headlight switch junction. The next time the problem occurred, I disconnected this junction and the headlights stayed on, which seemed to suggest that the steerring column switch was not the problem.

I have coped with this problem by disconnecting the battery whenever I had to leave the vehicle for extended periods of time. Now that the warmer weather has returned, I have gambled and left the battery connected, but the problem has not happened again. Somehow, it seems that power is being fed to the headlight relay in the engine compartment, but I have not been able to find what is powering this relay or why.

Any suggestions???

Poppadiesel

 

[rxshu]

Thats one of the oddest things I've ever heard of. On one of my uncle's vehicles (he's a car dealer) that he was letting me drive, I had a similar situation, except on mine it was the horn. Haha. I just disconnected the horn completely, but you cant do that with headlights, obviously. Sorry that was no help, but I thought I'd share that story with you.

 

[SilverBullet01]

possibly a bad relay in the fuse box? my guess.

otherwise you could take a voltage meter and see what wires are active during all of this fun

 

[Poppadiesel]

Weird headlight problem update

The problem occurred again today and this time I was able to get some more information. I disconnected the headliight switch junction (on the steering column) AND the igntion switch junction (lower on the steering column), in that order, and the headlights still remained on. Removing and re-installing the negative battery cable produced an audible relay clicking sound from below the fuse box in the engine compartment. Further testing showed that there were 2, similar, small relays, both with wires and vacuum lines below the fuse box on the inner fender (driver's side) next to one another. The one nearer the radiator would engage as soon as I re-connected the ground cable. This didn't always put the headlights on, however. For that to happen, the headlight relay in the fuse box had to engage, which it did every once in a while. When I disconnected the small relay nearer the radiator and re-connected the ground cable, there was no relay click and no headlights.

Does anyone know what these two small relays are supposed to do or what they are called? The suspicious one seems to get power independently of the ignition switch. Perhaps a weak spring allows it to engage, thereby turning on the headlights. With this relay engaged but no headlights on, the battery drain was in the order of .9 amps, definitely enough to kill the battery. I'm wondering if one of them might be the running headlight relay that automatically turns on your headlights when the engine is running. Perhaps the vacuum from the intake manifold is supposed to pull the relay in thereby sending power to the headlight relay which turns on the headlights. Can't find my Hayne's manual to check the schematics at the moment.

Any wiring harness gurus out with helpful ideas???

Cheers,
Roger

 

[SilverBullet01]

well since you can still run your headlights independent of your ignition being engaged, then i think the two relays may run at different times, but one of them may just be a bum relay somewhere in there. my guess is if you run voltage meters throughout the relays to see which one is active, and try and replace it

 

[Htbal0919]

1996 Toyota 4 runner headlight won't turn off

I have a weird issue with the headlights coming on after I shut the car, even though the headlight switch has been turned off. The only way I could turn it off and prevent it from draining my battery is to pull ht fuse. Could this possibly be a relay issue?

 

[spartacus]

I have a weird issue with the headlights coming on after I shut the car, even though the headlight switch has been turned off. The only way I could turn it off and prevent it from draining my battery is to pull ht fuse. Could this possibly be a relay issue?

please post when it's fixed.
start here
Headlights won't turn off, what's my issue?