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Old 05-23-2019, 09:37 AM   #1
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square body electrical problem???

on my way to work this morning i had a electrical issue pop up...
my dash lights went out and both blinker lights came on constant green,and the gas gauge dropped to empty...if i turn the lights off the gas gauge reads normal...before i start digging into this has anyone had a issue like this.? im thinking maybe a ground issue but i dont know where to start...and i hate lectrical...
Mongo...aka Greg

1981 C30 LQ9 NV4500..
Mongos AD- LS3 TR6060...
Columbus..the 1957 IH 4x4...
2013 GMC Z71..daily driver

Last edited by mongocanfly; 05-23-2019 at 08:54 PM.
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Old 05-23-2019, 06:38 PM   #2
Dead Parrot
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Re: square body electrical problem???

Some of your symptoms sound similar to this bad outcome:
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Old 05-23-2019, 06:56 PM   #3
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Re: square body electrical problem???

Look for a dash panel ground issue. Start by finding out how the dash panel is supposed to be grounded . I looked at a square body dash panel lying around and see there's a ground wire coming off the back...
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Old 05-24-2019, 10:44 AM   #4
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Re: square body electrical problem???

If the lights are causing issues that go away when you turn the lamps off... I'd check the forward lamp grounds on the LH & RH sides of the radiator support first. They're easy to get to and they may be the source of your headache. Make sure the star washers are still in place.

The two or three Black instrument cluster ground wires are spliced together around a few inches back in the harness from the cluster plug. You'll also find a splice in the Red/Black power wires with a single Red/Black wire running to the fuse panel but that's a much much much lower probability.

A single Black ground wire from that splice is supposed to run to a ring terminal on the glass fuse panel rigs or a Packard 56 Female terminal on the later rigs. Both terminate on a six tab 1/4" male buss bar or a ground screw on the kick panel just above the Parking Brake pedal.

Check the fastener holding the buss bar to the kick panel and check the Packard connectors to make sure they aren't loose. If someone removed the star washers from the ground fasteners replace them.

Be sure to properly cover exposed splices with self fusing low voltage splice tape like 3M Temflex. 3M Temflex is not Electrical tape... You stretch it to activate it and wrap it tightly around the connection while it's still stretched. It fuses into one airtight & watertight piece in a few minutes. If you remove and repair the splice adhesive "marine" heatshrink is easier to apply.
1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8

RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.

Last edited by hatzie; 05-24-2019 at 11:02 AM.
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