Lights No-Worky
- Thread starter Doc
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Doc said:
The headlight bulbs have dual filaments at two separate angles. If needed I could work up a procedure to analyze the filament firing angle, compare the results to the electrical schematic and tell you where the problem is in the circuit.
Cahil
- Thread starter
- #43
I put dielectric grease in the contacts, no lights.
Did not find a swappable relay for the headlights. But, after looking at the above diagram, I might try to find the tail light relay. It looks similar.
Did not find a swappable relay for the headlights. But, after looking at the above diagram, I might try to find the tail light relay. It looks similar.
Doc said:
Did you switch the lamps side to side to rule out possible bad lamp ?
Hmmm, problem is driver side circuit, most probable with the drivers side contacts to the headlamp. Could also be drivers side fuse related.
If you look at the schematic and theortically replace the drivers side fuse with a calibrated resistor, you would be able to duplicate your symptoms. Weird but possible. So somehow there's resitance on the drivers side of the circuit either as corrosion in a contact or toasted fuseable link.
Cahil
Assumptions on schematic: LH is drivers side and the internal dimmer switch is labeled wrong(HI & LO should be reversed)
Ok, here we go:
Go back to the schematic and look and find the LH headlamp.
From the LH headlamp go North to the fuse on the wire labeled RW(red-white).
Now from the LH headlamp go South on the RY(red-yellow).
The problem is somewhere along this piece of circuit, the connecting end points, or the headlamp contacts of this piece of circuit.
Somewhere in there, there is a resistance. Either a corroded contact or a partially blown fuseable link.
You are going to have to isolate those connecting points, contacts, and wires on the vehicle and start tracing.
Cahil
Ok, here we go:
Go back to the schematic and look and find the LH headlamp.
From the LH headlamp go North to the fuse on the wire labeled RW(red-white).
Now from the LH headlamp go South on the RY(red-yellow).
The problem is somewhere along this piece of circuit, the connecting end points, or the headlamp contacts of this piece of circuit.
Somewhere in there, there is a resistance. Either a corroded contact or a partially blown fuseable link.
You are going to have to isolate those connecting points, contacts, and wires on the vehicle and start tracing.
Cahil
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Doc said:
New one for me ... I've never had to deal with one. From what I've heard the wire casing will be deformed, twisted, bubbly, or basically ugly, not normal. Plus this section of wire *should* be easily replaced as it functions as an inline fuse.
Theoretically, from the schematic there shouldn't be any in this piece of circuitry ... but ?
Simplist thing to try is to get an automotive light probe. It will have a pointed pick on one end with light and a wire with an aligator clip on the other. Be sure you have one for automotive use which is rated for 12V.
Hook the aligator clip to vehicle ground, remove the headlamp, turn on the headlamps and probe the headlamp connector *carefully* to see if you can find current. Compare to the opposite side, and work from there.
The RW wire on drivers side should light the probe up.
Cahil
Yea, I'm with cahilc here. You need to probe the circuit either with a test light or a volt meter. Confirn +12 to both headlight sockets. I think you'll find that both have +12 since the hi beams work correctly. Then corfirm the grounds. The headlight plug has three prongs in the shape of a U. The middle of the U is the low beam ground. The other two prongs are +12 and the hi beam ground. Hopefully you'll find that one or the low beam grounds is flakey. That should hopefully narrow your problem to one wire. At the worst you could replace the ground by tapping into the same plug on the other headlight or you could toss in and aftermarket harness and bypass half of the OE harness. I'm not sure where the OE harness has the junction of the two lights - it could be at the switch or it could be elswhere in the wiring. HTHs
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- Thread starter
- #52
Sorry, no pics. I forgot!
Was not a fuseable link, the fuesable links (as I understand them) are right off of the battery terminals, not so far out as to be near the drivers side headlight.
Easy to replace? Well, if you call cutting/splicing/soldering/shrink wrappiing wires easy, yes. No more complex than a traditional wire splice I guess.
Was not a fuseable link, the fuesable links (as I understand them) are right off of the battery terminals, not so far out as to be near the drivers side headlight.
Easy to replace? Well, if you call cutting/splicing/soldering/shrink wrappiing wires easy, yes. No more complex than a traditional wire splice I guess.
Doc,
Really glad that you've got lights now. Any thoughts on what might have caused the short? Did the wire rub something that wore through the insulation maybe? Shorts don't just happen - there is a reason.
Best Regards,
Really glad that you've got lights now. Any thoughts on what might have caused the short? Did the wire rub something that wore through the insulation maybe? Shorts don't just happen - there is a reason.
Best Regards,
- Thread starter
- #54
Right, I'm sure sometime in the last 17-18 yrs those wires got rubbed against the lip around the headlight, which is sharp. Probobly took a few years of salt induced corrosion to fully short out. Or perhaps when I was installing the hella's I 'tweaked' the wires hard enough to make the break more apparent and likely to short.
At this point, it's a guess.
At this point, it's a guess.