Headlight woes (1 Viewer)

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Joined
Sep 17, 2011
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Location
Calgary, AB
Hey guys,

Got a weird problem with headlights.

Had drl's installed after purchase. Shortly after, headlights stopped turning on no matter what position the indicator was at. However whenever the headlights are not working the highbeam indicator is lit. However, while I'm driving, sometimes the headlights suddenly turn back on and the highbeam indicator turns off.

I swapped the drl relay that was installed and put a stock toyota relay. Problem is still there. Headlight relay clicks when headlight indicator is turned on.

Not sure where the problem is, is it the indicator? Or are there other junctions which can short and satisfy the highbeam circuit?
 
I know this isn't helpful for doing it yourself, but did the installer of the DRLs not offer some kind of warranty on their work? Sounds like they screwed up.
 
I wanted to make sure it was their install that screwed it up before I took it for warranty. That's why I switched their relay and went back to stock. Seems like it would have happened even if they didn't install drl's. Unless there's more to it than a relay in the fuse box.
 
Arighty, so did some work on this problem.. getting dangerous while driving at night with only fog lights.

Took off the headlight and tested the 3 wires on the harness: red-yellow, red-white, red-green.

When the low beams are turned on, all 3 wires carry 12 V. This explains why I dont have headlights and why the highbeam indicator is on.

I looked for a junction on a wiring diagram my buddy sent me:

IMG_0597.JPG


My best guess is that all 3 wires are shorting to eachother in the DIMMER SW (near lower middle of diagram). Which explains why R-W, R-Y, and R-G all have 12 V.

Anyone have problems with the dimmer switch assembly like this?? I took it apart and it looks like these wires converge into a factory sealed box... looks like I may need a used unit though I'm curious on experiences here.
 
Haven't seen this problem caused by the dimmer switch. My dimmer switch stopped working after I replaced some normal interior bulbs with LEDs but it has no impact on my headlights.
 
Wait! Look at the diagram, the power is supplied to the one input at the bulb. The switching portion of the circuit needs to ground either the low beam side or the high beam side to turn the bulbs on. The reason you have 12v at all terminals is no ground is occurring (thus no illumination).
Follow diagram to the ground location, understand the. Irkutsk befor further testing.
The diagram shows a triangle with a letter in it on right and left of the print.....find the same triangle and letter on next page, follow to the ground symbol, like is shown on battery.
Then text for where power continues......likely the switch is not closing that leg to ground....or no ground d is present at end of circuit......keep learning, keep testing, stop swapping parts until you understand the circuit.
 
Wait! Look at the diagram, the power is supplied to the one input at the bulb. The switching portion of the circuit needs to ground either the low beam side or the high beam side to turn the bulbs on. The reason you have 12v at all terminals is no ground is occurring (thus no illumination).
Follow diagram to the ground location, understand the. Irkutsk befor further testing.
The diagram shows a triangle with a letter in it on right and left of the print.....find the same triangle and letter on next page, follow to the ground symbol, like is shown on battery.
Then text for where power continues......likely the switch is not closing that leg to ground....or no ground d is present at end of circuit......keep learning, keep testing, stop swapping parts until you understand the circuit.

Right, isn't that what I am already suspecting?

There are 2 variables left:

1: Switch not providing ground, thus supply from Red-White is crossing to all wires. (Which is why I was asking if people have had known problems with this switch)

2: White-Black from switch to ground not sufficient. This is located at right kick panel on my HDJ. Do all these wires common ground at common junction (location-wise)?
 
Sorry, I should explain more, all 3 wires at dimmer will have batt power when the headlamp switch is not providing ground to the w/r wire, ie....off or failed switch. Another way to turn them on would be to pull the flash to pass dimmer sw. Thusly grounding the w/r wire (through the w/b wire)
That should help you determine if the w/b wire is simply not a good ground or you have a failed switch.
 
Sorry, I should explain more, all 3 wires at dimmer will have batt power when the headlamp switch is not providing ground to the w/r wire, ie....off or failed switch. Another way to turn them on would be to pull the flash to pass dimmer sw. Thusly grounding the w/r wire (through the w/b wire)
That should help you determine if the w/b wire is simply not a good ground or you have a failed switch.

Took a look under the kickpanel, ground looked fine.

I am beginning to suspect failed switch as "flash" position works, but the middle and highbeam positions do not. I go from no headlights, then pull the switch to the flash position and they come on. If the ground was bad, then the flash position would NOT work, correct?
 
Finally found the solution to this problem:

Took apart the double electrical connector harness under the steering column. There were shavings inside which I simply blew out, and suddenly my lights worked! I'm assuming the ground was getting shorted at that point.
 
wow! how did those get there you think?
 
wow! how did those get there you think?

Not a clue! There was a surprising amount of debris inside the connector. The previous owner (in Japan) did quite a bit of fooling around with the electrical and now I'm cleaning up their mess.

I was so close to ordering a replacement indicator switch too... good thing I took apart the connector!
 
Just confirmed it's the connector. The problem started again and I went ah s***. Luckily I didn't put the bottom trim back on and wiggled the connector and boom, lights went back on.
 

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