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| | | | Joined: May 2010 Posts: 162 'Bolter | | 'Bolter Joined: May 2010 Posts: 162 | I recently had a new fuse block and new under dash harness kit installed. The lights worked for a while but have stopped working. New headlight switch and dimmer. Should there be power to the dimmer switch with the headlight switch on?
Thanks in advance,
Mark | | | | | Joined: Jan 2022 Posts: 2,435 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,435 | If the "new fuse block and new under dash harness kit" is anywhere close to the original wiring diagram, yes there should be power to the dimmer switch when the headlight switch is pulled all the way out.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Oct 2021 Posts: 6,684 'Bolter | | 'Bolter Joined: Oct 2021 Posts: 6,684 | I rewired my headlights from the dimmer switch to the headlamps a couple years ago. Prior owner had the three wires on the dimmer mixed up so lights only worked on hi beam.
What year and model are you working on?
If it is 6v, you must use 12ga wire as a minimum.
Do the headlights work at all on either hi or lo beam?
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
| | | | | Joined: May 2010 Posts: 162 'Bolter | | 'Bolter Joined: May 2010 Posts: 162 | 12volt. 1960 C-10 No. I have no power at all.
Thanks,
Mark | | | | | Joined: May 2010 Posts: 162 'Bolter | | 'Bolter Joined: May 2010 Posts: 162 | Well it should be. A reputable mechanic that has done work for me in the past installed it. I was trying to troubleshoot a little because they didn’t touch the headlight harness. The headlight wires from the connector on the firewall to the connector on the core support have continuity so I don’t think it’s the headlight harness.
Thanks,
Mark | | | | | Joined: May 2015 Posts: 10,997 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 10,997 | Start at your fuse block and see if you have power to the circuit feeding the headlight switch, then check with the switch on at the output wire, then down the line toward the dimmer switch and headlights. When you get to the point where you have no power, back up and fix that component.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Jan 2022 Posts: 2,435 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,435 | Question: Do any other lamps that run off the headlight switch work? Dash, tail, parking?
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: May 2010 Posts: 162 'Bolter | | 'Bolter Joined: May 2010 Posts: 162 | Turns out I had a bad switch. Thanks everyone for your advice.
Mark | | |
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