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Old Apr 16, 2013 | 06:34 PM
  #16  
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Mowing Man
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From: Quaker Hill
Sorry Dave, just got home from work and read your post. Glad you got it figured out. Like Rich said, its a slim chance that was a problem, but in my case, I'm extremely unlucky. I've had 2 electrical shorts that drove me nuts on my flatbed, and was one of the few that have had a glow plug swell up, resulting in having to pull a head to remove it. In my case, if someone tells me, 'It's a slim chance this could happen,' I usually start there, especially if its easy to check. Too bad my luck only works like that on bad things and not the lotto! Anyway, glad you got it figured
 
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Old Apr 18, 2013 | 10:14 AM
  #17  
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Originally Posted by Tugly
Unplug the alternator and with your meter set to volts DC, connect your red probe on the wire that is light green with a red trace, and the black probe on a good ground. Make certain you have good electrical connection to both. Turn your ignition key to run, but do not start the truck. If you have 12 volts on the meter, your alternator is triggering the light. If you do not have 12 volts, it's party (and troubleshooting) time.
Tugly....I did the test and have 11.45volts with the KOEO and .2 volts with the key off....with 11.45 volts triggering the light does that mean the alternator is good or bad? Do I need to troubleshoot farther or R&R the alternator?

Jeff
 
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Old Apr 18, 2013 | 12:03 PM
  #18  
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Originally Posted by koski19
Tugly....I did the test and have 11.45volts with the KOEO and .2 volts with the key off....with 11.45 volts triggering the light does that mean the alternator is good or bad? Do I need to troubleshoot farther or R&R the alternator?

Jeff
  1. The light is suppose to come on (everything connected) until the engine is running.
  2. The test above was just to make sure the volts went high on the the wire I mentioned (high is good on a disconnected regulator with KOEO and low is good with key off).
If your battery light is coming on with everything connected and engine running, after the test results above... it's alternator time.
 
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Old Apr 18, 2013 | 01:01 PM
  #19  
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Originally Posted by Tugly
  1. The light is suppose to come on (everything connected) until the engine is running.
  2. The test above was just to make sure the volts went high on the the wire I mentioned (high is good on a disconnected regulator with KOEO and low is good with key off).
If your battery light is coming on with everything connected and engine running, after the test results above... it's alternator time.
I R&R'd the alternator with a new Napa unit. AE shows 14.3 volts charging after 5 minutes of idle time. Load system with lights on and AC at max voltage drops to 13.1. Rev engine to 2100 RPM voltage rises to 14.2.....

Jeff
 
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Old Apr 18, 2013 | 02:57 PM
  #20  
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All is well... good job!
 
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Old Apr 18, 2013 | 03:41 PM
  #21  
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From: Longview, TX
I had the same thing on Gus about 2 years ago during a trip to LA (that's the mudhole, not the city). Noticed the light but everything was ok so I ignored it. Driving home in bad weather the whole way with lights and wipers and the radio all running full blast, I started to see issues. Wipers got REALLY slow, radio went out, dash shut down, and I was thinking "it's a diesel so as long as I don't turn it off, I'll be ok". Then I realized I'd need to get fuel from the tank to the injectors and found an oreillys. Changed it in the parking lot and got a jump and went on my way.
 
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