High Beams don't Work, Low Beams do.
June 27th, 2017, 8:49 AM
#1
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High Beams don't Work, Low Beams do.
This is a problem that's giving me fits.
I recently bought a 2001 K2500 Suburban that is a retired Fire Department Battalion Chief's vehicle. Most of the EMT-specific mods have been removed or cut and left. Thankfully, most everything works except for the horn and High Beams. The horn is an issue I'll deal with separately. I'm just looking for advice on the High Beams.
Right now the low beams work fine, but when selecting high beams the lights go out altogether. I realize the factory wiring turns off the Low Beams when the High Beams come on so at least part of the circuit seems to be working correctly. Whenever the lights are selected on the High Beam indicator is lit. I changed the bulbs, checked the headlight fuses, and replaced the relay. No change. Then I replaced the dimmer/turn signal/wiper/hazard multi-switch. Again, no change. I've considered that the Fire Truck mods might have included some alteration to the High Beam wiring, but there's nothing obvious to suggest that. I would expect different wiring and some additional relay. If it's there I haven't found it. I've got the correct Haynes Manual and have combed over the wiring diagrams. Everything LOOKS correct.
Anyone got any ideas what I should try next?
I recently bought a 2001 K2500 Suburban that is a retired Fire Department Battalion Chief's vehicle. Most of the EMT-specific mods have been removed or cut and left. Thankfully, most everything works except for the horn and High Beams. The horn is an issue I'll deal with separately. I'm just looking for advice on the High Beams.
Right now the low beams work fine, but when selecting high beams the lights go out altogether. I realize the factory wiring turns off the Low Beams when the High Beams come on so at least part of the circuit seems to be working correctly. Whenever the lights are selected on the High Beam indicator is lit. I changed the bulbs, checked the headlight fuses, and replaced the relay. No change. Then I replaced the dimmer/turn signal/wiper/hazard multi-switch. Again, no change. I've considered that the Fire Truck mods might have included some alteration to the High Beam wiring, but there's nothing obvious to suggest that. I would expect different wiring and some additional relay. If it's there I haven't found it. I've got the correct Haynes Manual and have combed over the wiring diagrams. Everything LOOKS correct.
Anyone got any ideas what I should try next?
June 27th, 2017, 1:18 PM
#2
They probably installed wig-wags on that vehicle. That turns the high beams on and off like the emergency equipment. probably an issue in that circuit. Turn on the high beams and trace the circuit backwards.