1991 toyota pickup with one dim/dull headlight. Flipping between high/low had no effect on the light. Thought it may be the filament so I went ahead and got the ebay H4 conversion housing and bulbs and threw them in the truck. Same issue

The one headlight was still dim and no change with high/low toggle (the other works just as it should).
Checked the current on the bad headlight connector with a meter and the connector positve is pulling 12 volts. Checked the ground with one of those little check lights and it was fine. good ground.

So the connector is putting out power, and the ground checks out. But the light is still dim.

Whats the problem here?




I know this has been discussed - as I have searched but I am a bit stumped. I don't think it is the combo switch.


anyways - I think I may may the 4crawler wiring harness located here: http://www.4crawler.com/4x4/CheapTri...OnLineOrdering
But thought I would see if I can resolve this without the extra money.

 

Your connector has voltage but no power. This means that you probebly have a bad ground. Voltage does not mean current. Because you have one good light I would say that you have a bad connector, or wiring going to the High/low relay in the box with the fuses. Does it switch to high beams?

 

No, the bad light, doesnt switch to high beams. Toggling the switch has no effect on the bad light.

As far as the ground, I used a little check tool, basically a screwdriver with a light inside. connect the positive and the ground to a connector and the light lights up bright if the ground is good. I think thats how it works at least. Did that and it lit up fine.

**Oh, also I set up another ground to the frame and then spliced into the ground connector on the bad light, but it had no effect.

 

Toyota headlights work by grounding the given filament via the headlight combo/dimmer switch on the steering column:
- http://www.4crawler.com/4x4/CheapTri...l#HarnessTypes

Probably have a wiring issue someplace between that bad socket and the switch.

 

i have the same problem

i changed lights and plugs to the lights and wired them correctly.

 

roger can I order the H4 harness from you? (it is listed as out of stock on your site.)


Would that even solve my problem? or do I still need to go and mess with the combo/dimmer switch before switching out the harness?

 

Yes, as long as you have enough of a wiring connection to turn the relay on and off (about 0.1 amps vs. 10+ amps for the actual lights, say from the working side), then the harness would bypass the rest of the wiring.

Yes, the H4 harness is out of stock, three options are to order the 9004 harness and either splice it into your existing wiring (cutting off the 9004 connectors and splicing the harness to the existing H4 connectors). Or for a plug in version, order the H4 male and female connectors and put them on the 9004 harness, or that can be supplied pre-wired and tested.

 

Small hijack here but maybe one of you can help. This is on my 89 4runner.

I have low beams no problem. If I pull the blinker lever back and hold it I have hi beams. When I push the blinker lever forward the head lights go out. Thoughts?

 

Sounds like a bad headlight switch. Have to test it to be sure.

 

Yep, X2 on the headlight combo switch, likely dirty or pitted contacts, see below for details:
- http://www.4crawler.com/4x4/CheapTri...eadlight_Combo