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  #1  
Old 03-09-2013, 09:41 AM
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Electrical gremlins

So I'm driving along in the 88' waggy and I notice the radio has stopped working. A quick look at the voltmeter shows we're down around 8 the headlights are also out and upon restart I hear what I think is one of the two circuit breakers tripping. Help?
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Old 03-09-2013, 12:48 PM
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Start with the basics...

Check battery cables, check alt. belt tension and wiring.
Swing into a parts store or repair shop and have the system tested.
Good ones will do it free of charge.
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Old 03-09-2013, 01:08 PM
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Fusible link between alternator and battery.
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Old 03-09-2013, 01:30 PM
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Thank you all, I checked the fusable links all good. I'm going to take it to a mechanic. I suspect a problem with the alternator but the headlights and radio going away suggests something bigger.
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Old 03-09-2013, 01:57 PM
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I'm electron impaired for electrickery diagnostics but I'd start with checking that all related grounds are clean and tight.
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Old 04-14-2013, 12:35 PM
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Alternator checked out fine... going to go looking for bad grounds...
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Old 04-14-2013, 12:53 PM
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Quick test. With the motor running and lights on, take jumper cables (careful of the fan!) and jumper from the battery negative to the rad support or metal on the grill. If the lights get brighter, you found the problem!
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Old 04-14-2013, 05:16 PM
Joe Guilbeau Joe Guilbeau is offline
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[quote=cheiler]Alternator checked out fine... going to go looking for bad grounds...[/QUOTE

Try this procedure...

http://oljeep.com/AltTheory17/AlternatorTheoryVersion17R1.htm#Testing_Alternator s
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Old 04-15-2013, 09:54 AM
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I had the alternator tested 14.7v output. put it back in and cleaned connections and battery terminals. no change. dash voltmeter shows 10and dropping. Headlights still will not light and still no radio. tried new 30a circuit breaker no change. I'll give the other tests a try.
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Old 04-15-2013, 09:56 AM
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Quote:
Originally Posted by Carnuck
Quick test. With the motor running and lights on, take jumper cables (careful of the fan!) and jumper from the battery negative to the rad support or metal on the grill. If the lights get brighter, you found the problem!
No lights, they no longer come on.
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Old 04-15-2013, 03:00 PM
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On the side plug for the alternator, there are 2 wires. One will be always live and the other will go on/off with key and have lower voltage (it passes through a 10 ohm resistor) If that one doesn't get power, the alt won't engage.
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Old 04-15-2013, 04:50 PM
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Nope

Not the alternator plug. Maybe the firewall plug or the splice under the dash where the big red wire connects from the alternator. Next in line would be all grounds. from the battery to the firewall.
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Old 04-15-2013, 07:57 PM
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I was going to say if there are no headlights, the splice melted. Try a thick jumper wire from the back of the alt main terminal to the battery +
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  #14  
Old 04-26-2013, 03:56 PM
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Quote:
Originally Posted by serehill
Not the alternator plug. Maybe the firewall plug or the splice under the dash where the big red wire connects from the alternator. Next in line would be all grounds. from the battery to the firewall.

The plug at the alternator was gone when we bought her. it's just two wires now. I'll check the splices.
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Old 04-26-2013, 07:14 PM
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sounds like the engine is getting a ground and the body is not.
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Old 04-28-2013, 04:15 PM
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You probably have 1 of 3 problems.

1. Your grounds need to be replaced.
--I ran one directly from the battery to the engine block and another directly from the battery to the body. My grounds work great now!!

2. Your alternator plug is poorly spliced. They sell replacement plugs in the help section of the autoparts stores..

3. There is another fusible link in the cable between the alternator and the battery. Even though it checks good with an ohm meter, it could still be bad. Old fusible links are prone to this -- high charging current heats up a mostly burned up link increasing the resistance and prevents the charge from getting to the battery. I cut mine out and replaced it with a 100 amp fuse...

If you want some hands on help with this, PM me.
I am quite good at electrical/electronic repairs and I am only a few miles from you..


Hope this helps
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  #17  
Old 05-19-2013, 09:51 AM
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Thank you, I may take you up on that. I'm going to recheck the fusible links and bottle some beer. I'll let you know if I need a hand with the waggy and getting some of that beer back out of the bottles.
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Old 05-19-2013, 11:30 AM
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Found a bad fusible link, have headlights back but now the engine won't turnover. hear the solenoid click but no starter... ugh
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  #19  
Old 05-19-2013, 11:57 AM
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ITS RUNNING AND CHARGING THE BATTERY AND IT HAS HEADLIGHTS!!!!!
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  #20  
Old 05-19-2013, 12:28 PM
joe joe is offline
 
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Quote:
Originally Posted by xGROMx
sounds like the engine is getting a ground and the body is not.
That's the direction I'm leaning. All the dash stuff that's grounded to the body relies on the body being well grounded to the frame which is just grounded to the chassis via the body mounts. After 25 years in MD salt slush don't expect the body mounts to still be good electrical ground connections. I've had wonky gauge, lights etc issues in the past. Remove a bolt holding something to the firewall or use an empty hole. Sand the paint off the sheetmetal and run a ground wire from the battery to the clean spot on the firewall. You don't need a battery cable size wire. A good secure piece of 08 or 10 ga is plenty. Clean tight grounds are your friends.
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