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#94525 02/05/2006 9:56 PM | Joined: Jul 2005 Posts: 50 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2005 Posts: 50 | Ok guys don't laugh. When I first got this truck (51 Chevy 3100), I hooked up a 12 volt battery on a 6 volt system. Headlights and turn signals that were working stopped. Since I have gotten the correct battery, replaced headlight bulbs, 2 fuses inside engine compartment and turn signal fuse inside cab. Headlights and turn signals still aren't working.
Parking lights, dash lights and interior work fine so I don't think it's wiring. Plus they were working before I did the dumb battery thing.
What am I missing?
1951 Chevy 3100 w/235
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#94526 02/05/2006 11:32 PM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | magnmike,
I wonder if your headlight switch is a fused style. I researched it a bit, and it says the stock switch wasn't fused, but some of the replacements were.
Stuart | | |
#94527 02/06/2006 4:56 AM | Joined: Jul 2005 Posts: 50 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2005 Posts: 50 | I believe it is a stock part. Looks like original wiring too. I'll look for another fuse though. Thanks.
1951 Chevy 3100 w/235
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#94528 02/06/2006 6:17 AM | Joined: Apr 2002 Posts: 1,571 Shop Shark | | Shop Shark Joined: Apr 2002 Posts: 1,571 | The original headlight switch wasn't fused, and will happily take 12v power. It's darn near bulletproof. If there was a headlight relay installed for some reason, you could have nuked that. | | |
#94529 02/06/2006 7:21 AM | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy guys, did you replace the flasher unit, what about the tail light/turn signal bulbs? give the dimmer switch a couple of high/low cycles that might clean it. | | |
#94530 02/06/2006 4:45 PM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | magnmike,
I looked at the only wiring diagram I could find. I was for a '54 truck, so It might not be accurate for your truck.
There is no common connection between headlights and turn signals. Turn signals are brake lights that utilize the flasher to blink them. If you have brake lights but no turn signals, this would indicate a flasher problem as 3B mentioned.
If everything worked before you installed the 12 volt battery, and it doesn't work now, it would appear to be a fusing problem. You have stated you replaced three blown fuses, but it still doesn't work.
Merely installing the battery wouldn't blow the fuses unless you energized that circuit. The brake lights connect to back of the headlight switch, but only as a connection point...they aren't switched.
Something is rotten in Denmark..keep looking.
Stuart | | |
#94531 02/07/2006 4:38 AM | Joined: Jul 2005 Posts: 50 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2005 Posts: 50 | Haven't replaced the flasher yet on the turn signals. Went by NAPA but they only have a 12 volt flasher. A 6-volt flasher is on there now. Can you use a 12-volt flasher on a 6-volt truck?
1951 Chevy 3100 w/235
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#94532 02/07/2006 5:40 AM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | magnmike,
I think the first plan would be to see if you have brake lights...just step on the brake and have someone holler yea or nay. If the 6v flasher is in the rig, flip the handle to indicate a turn while holding the flasher...can you feel it or hear it respond. Have you checked the brake light bulbs yet.
I will give you the usual comments on the little circuit tester with the pokey end and bulb inside...a indispensable item when doing work such as this, and cheap too. Keep searching.
Stuart | | |
#94533 02/07/2006 12:36 PM | Joined: Feb 2006 Posts: 395 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 395 | check all bulbs that were turned on with 12 volts could be burned out...You will have to use a 6 volt flasher..Head light sw arenot fused for the head lights they have a curcit breaker,,some have a fuse on the sw for dash lights but not for head lights.... | | |
#94534 02/07/2006 6:41 PM | Joined: Apr 2002 Posts: 1,571 Shop Shark | | Shop Shark Joined: Apr 2002 Posts: 1,571 | They weren't fused or relayed from the factory...but things get changed in the span of 50+ years. | | |
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