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| | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | Help!!! Just turned on my headlights and gauge just pegged to discharged,went to park and returned to normal. Any sugestions????? | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | use an ohmeter to check all the wiring for starters, likely be a shorted wire between the switch and the lights, not likely the actual switch
Bill | | | | | Joined: Jun 2006 Posts: 687 Shop Shark | | Shop Shark Joined: Jun 2006 Posts: 687 | red58 I know what you ment to say but as it is written you have this guy checking his starter wiring. LOL
I didn't do it, no one saw me do it, you can't prove anything! "Bart Simpson"
| | | | | Joined: Jun 2006 Posts: 687 Shop Shark | | Shop Shark Joined: Jun 2006 Posts: 687 | So splain this to me a bit more. You turned the headlamps on and the amp meter went to complete discharge and stayed untill you went back to the running lamp position (park). Is that right? Did you turn them on again? If so what happened? Are they ok now or do you still have the problem?
I didn't do it, no one saw me do it, you can't prove anything! "Bart Simpson"
| | | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | still have the problem even after I turned them off and went to park lights.only happens with headlights on.Checked all wiring no grounds. | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I don't know what year of truck you have but the dimmer switches can cause big problems. If you were checking for shorts to ground I would be checking the wire that goes from the headlight switch to feed the dimmer switch, with everything still attached. If you start to remove wires you might alter the problem. | | | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | It's a '53 6100 with 12 volt generator conversion,I might have a
6 volt switch but I don't know,I could check with my ohms meter if I knew what my readings should be. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | voltage doesn't matter for switches, will work the same with 6 or 12 - should be open on one set of contacts [the "off" side], dead short on the other [the "on" side], opposite when switched
Bill | | | | | Joined: Jun 2006 Posts: 687 Shop Shark | | Shop Shark Joined: Jun 2006 Posts: 687 | Ok, so you either have a dead short or weak amp meter. Most old trucks have a fuse built onto the side of the switch. Remove this fuse and try turning the headlamps on again. Do you get the same result? If so you may have a faulty switch if not install the fuse and goto the headlamp dimmer switch on the floor. on this switch you will have 3 wires, one gos to the headlamp switch the other 2 are for high and low beam. Before we test (just for grinns and giggles) mash the dimmer 1 time and try the headlamps again. Did the meter peg out? I am stoping here for a reply.
I didn't do it, no one saw me do it, you can't prove anything! "Bart Simpson"
| | | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | Did'nt matter what I did with the dimmer,but if I leave them on for a while they start to flicker like I'm turning the switch on and off. | | | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | almost for got could'nt find a fuse. | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | PapaJ,
Don't rule out the voltage regulator. It might have funky points that aren't allowing the generator to kick into charge when the headlight load is applied. A massive discharge indicated by the ammeter would produce smoke and fire if it were a short. If it were merely a heavy draw on the battery caused by a 'no charge' situation in the charging system, it would go on until the battery was dead...no fire-no smoke.
Stuart | | | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | New voltage regulator,new battery still draws.Generator was putting out good voltage too. | | | | | Joined: Jun 2006 Posts: 687 Shop Shark | | Shop Shark Joined: Jun 2006 Posts: 687 | Sounds like your switch has a circuit breaker built in. I don't know what year they started that but all headlamp switches after a certain year have a built in circuit breaker. It will get weak and start shorting out. You can't do much to test this but you can look over the wiring system for any obvious damage and replace the switch.
I didn't do it, no one saw me do it, you can't prove anything! "Bart Simpson"
| | | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | After back surgery and dealing with legal stuff I got to return to my light switch.Turns out I'm an IDIOT,I cut the electrical tape off of the"wiring harness" and found a bunch of exposed wires for the headlights.So now that I know what the problem is I can fix it!(just a few slaps upside my head.) | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | The AD series of trucks had a thermal breaker built into the head light switch.
Good luck on your repair and I hope you are feeling better. | | | | | Joined: Feb 2009 Posts: 400 'Bolter | | 'Bolter Joined: Feb 2009 Posts: 400 | Just have to rewire at the terminal block to the headlights. | | |
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