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Bob wood (66.208.219.185)

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Posted on Tuesday, September 09, 2003 - 1:46 pm:   

Hi All,
I need some help with a voltage problem in an Eagle 20. Here's the problem: The volage supply (12Vdc) that feeds the instrument gauges, Air dryer, Dixson Speedo, A/C Relay coil, and the voltage regulator, is fed through a 20amp CB off the ignition/battery switch, which pulls a relay on the output side of the 20amp CB, and the voltage flows. Intermittently, the 12 volts drops to 4 volts on this supply buss, and of course all the gauges stop functioning, the speedo stops, and no voltage regulator. Here is what I've done so far to isolate the problem: 1)replace CB--no change. 2) remove AC relay from it's socket--no change. 3) remove air dryer wire--no change. My next step is to remove all the gauges, and the dixson speedo. The weird think about this whole problem is every time I do something, the problem goes away, I drive for 30-500 miles with no problem, and then all my gauges go dead, and the voltage is reading 4 volts on the buss. Very frustrating. I know it very hard to help someone troubleshoot over the BB, but does anyone have experience with this same problem on their coach, or have you heard of this problem on other threads. Thank you.
Bob.
two dogs (67.30.23.126)

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Posted on Tuesday, September 09, 2003 - 1:55 pm:   

I'd say it was a loose wire Bob...on the alt. or somewhere in between...if the front of the bus is all you are messing with ...& it "heals" (temporarily).....I'd guess it was up front
Gary McFarland (Gearheadgary) (209.128.79.46)

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Posted on Tuesday, September 09, 2003 - 2:02 pm:   

Mr. Two Dogs beat me to the punch--

I think you've got a dirty connector, that you bump when you're making changes, and returns to it's bad connection state after a while.

I'd check all your connections, especially any Crimps.

Also, if you have any "Molex" multi-conductor style connectors look fot a pin that has "Backed out" of the plastic connector.

Good luck.

Gary
Richard Bowyer (Drivingmisslazy) (24.196.191.70)

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Posted on Tuesday, September 09, 2003 - 2:23 pm:   

Also actually remove the nutted connections and check for corrosion. I agree with the others is that it is a loose or corroded connection.
Richard
Gary Stadler (Boogiethecat) (68.7.217.217)

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Posted on Tuesday, September 09, 2003 - 2:30 pm:   

...and where are you measuring the minus side of the voltage from? If you're sticking your black voltmeter lead to ground, right on the instrument console itself, it's possible that the whole console is not well grounded due to loose screws, etc. Thus even though the voltmeter might be showing 4 volts, the actual 12 volts might be ok and it's the ground side that is the culprit...

Gary S
Richard Bowyer (Drivingmisslazy) (24.196.191.70)

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Posted on Tuesday, September 09, 2003 - 2:34 pm:   

Excellent point Gary. My console is actually made of wood so a good ground must be run back to chassis ground. The instruments are effectively isolated from chassis ground.
Richard
Gary McFarland (Gearheadgary) (209.128.79.46)

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Posted on Tuesday, September 09, 2003 - 2:37 pm:   

Yes, good point--you could just cut to the chase by putting in a new ground wire.

BTW: How many guys named Gary are on this list anyway?

(Gearhead) Gary
Don KS/TX (66.82.9.16)

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Posted on Tuesday, September 09, 2003 - 3:51 pm:   

I think you are on it Gary, I had the same problem driving me nuts for a while until I found it to be a faulty ground.d
Brian James Houk (Brianmci96a3) (65.41.249.35)

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Posted on Tuesday, September 09, 2003 - 11:19 pm:   

As a diesel mechanic of 23 years I'd have to agree with Gary. I would be highly surprised if it was something besides a bad ground.
Jayjay (198.81.26.104)

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Posted on Tuesday, September 09, 2003 - 11:34 pm:   

Another place to look: do you have a wire broken off back up inside the insulation? Near terminals is where it usually occurs, give it a good stout pull, or move it side to side and watch the volt meter. Sometimes you can feel the "narrow" spot in the wire by running your fingers along it. It'll get skinny where the break (or partial break) occurs. This is a tuffy, so let us know what it turns out to be. BTDT...twice! Good Luck and Cheers...JJ

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