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Instrument short? [message #278276] Sun, 24 May 2015 07:02 Go to next message
misnomer is currently offline  misnomer   United States
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My gauges and dash lights went out in my 77 Birchaven with a 455 yesterday. I replaced the fuse only to lose another. Started probing around with my meter to find 0.0 ohms between the low side in the fuse box and ground. So, I've got a short somewhere. Are there any common problem components or wires in the dash I should start my search with?

77 Birchaven 23 w/ 455 Reno, NV
Re: Instrument short? [message #278288 is a reply to message #278276] Sun, 24 May 2015 11:40 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Remove the turn signal/parking light bulbs at the four corners one at a time, check for your short after you remove each one. If the fuse output is still shorted, the clearance lights are the next easiest to remove and check. After that your left with looking for wires that got loose and hung up in the A/C controls, or were hanging and swinging from light bulb sockets, and anywhere there is movement that is connected by wires, like tilt steering wheels and door jamb boots and any wires that have to flex frequently between mounted parts.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: Instrument short? [message #278289 is a reply to message #278288] Sun, 24 May 2015 11:43 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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And get the schematic so you can see everything that GM connected to that fuse and check those items too, by disconnecting them and checking for that short after EACH change you make.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: Instrument short? [message #278290 is a reply to message #278289] Sun, 24 May 2015 11:44 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Very handy to use a buzzer or a tone generating multimeter for this type of search and find mission.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: Instrument short? [message #278300 is a reply to message #278276] Sun, 24 May 2015 14:13 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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misnomer wrote on Sun, 24 May 2015 07:02
My gauges and dash lights went out in my 77 Birchaven with a 455 yesterday. I replaced the fuse only to lose another. Started probing around with my meter to find 0.0 ohms between the low side in the fuse box and ground. So, I've got a short somewhere. Are there any common problem components or wires in the dash I should start my search with?
To abbreviate what BullitHead is saying, the dash lights are on the same fuse as the tail lights so that the dash lights go out when the tail lights blow the fuse. It was done on purpose by the manufacturer to alert the driver to the problem. So your problem might be with the tail lights, and not the dash circuitry.
Re: Instrument short? [message #278302 is a reply to message #278300] Sun, 24 May 2015 14:48 Go to previous messageGo to next message
Hal StClair   United States
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And if the coach has an owner added plug for a trailer/toad that is tapped into the tail lights, that would be a prime area to look.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: [GMCnet] Instrument short? [message #278303 is a reply to message #278300] Sun, 24 May 2015 15:19 Go to previous message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Read here
http://gmcmotorhome.info/chassis.html#Rear
And if you changed the radio recently
Read that too

Let us know

On Sunday, May 24, 2015, A. wrote:

> misnomer wrote on Sun, 24 May 2015 07:02
>> My gauges and dash lights went out in my 77 Birchaven with a 455
> yesterday. I replaced the fuse only to lose another. Started probing around
> with
>> my meter to find 0.0 ohms between the low side in the fuse box and
> ground. So, I've got a short somewhere. Are there any common problem
> components
>> or wires in the dash I should start my search with?
> To abbreviate what BullitHead is saying, the dash lights are on the same
> fuse as the tail lights so that the dash lights go out when the tail lights
> blow the fuse. It was done on purpose by the manufacturer to alert the
> driver to the problem. So your problem might be with the tail lights, and
> not
> the dash circuitry.
> --
> '73 23' Sequoia For Sale
> '73 23' CanyonLands For Sale
> Upper Alabama
> After all is said and done, a helluva lot more is said than done.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>


--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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