Electrical problem 79'

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Oct 28, 2018 | 06:29 PM

Duke94

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From: Ann Arbor Michigan

Electrical problem 79'

Almost finished with the restoration of my 79. Figured I better start testing the electric stuff before everything is buttoned up. So I attached a 12V power supply to the batt cables and reduced the voltage to limit the current output to 2 Amps max. When I turn the power supply on, it shows 2 Amps draw with everything turned off.
The following was noted:
>Dome light always on (doors closed) headlight switch no effect.
>Backup lights always on even with switch removed. Right side very dim, left side normal.
>Horn blows (the steering wheel is not installed.
I installed a new forward lamp harness and engine harness.
Dash harness is original.
I have pulled every fuse along with the turn signal switch and nothing changes, still shows current draw.

Clearly something is not connected right, but everything on the new wire harnesses was plug and play. Ground wire missing?
Where do I go from here??

Thanks

Oct 28, 2018 | 07:36 PM

Duke94

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From: Ann Arbor Michigan

Did a little more checking and narrowed it down to what ever is on the dome light fuse. If I pull just that fuse, everything is OK. When I plug the fuse back in, the horn blows, dome light stays on and the backup light come on.

Oct 29, 2018 | 10:29 AM

henrikse

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From: Kelowna British Columbia

I would remove the horn wire and see if this solves your trouble. When you get the steering wheel back together horn probably draws this kind of current. Both courtesy lights are on this circuit as well as the alarm

Oct 29, 2018 | 12:07 PM

Duke94

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From: Ann Arbor Michigan

Quote:

Originally Posted by henrikse

Pulled the horn wires but still have the dome lights and BU lights on. Will dig further into it tonight.

Thanks.

Oct 29, 2018 | 09:48 PM

henrikse

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From: Kelowna British Columbia

Dome lights are hot all the time. You get ground from the passenger side door switch which jumpers to the drivers side. If your bu lights are on perhaps the courtesy lights are picking up ground from here or the 12 volts for the two circuits is together. Since the dome is hot all the time the wire from the bu lights is probably touching it somewhere

Oct 30, 2018 | 10:59 PM

righthanddrive

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From: colo

Do you have a delay on the interior lights ?

Oct 31, 2018 | 09:09 AM

Duke94

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From: Ann Arbor Michigan

Quote:

Originally Posted by righthanddrive

Do you have a delay on the interior lights ?

Yes I do, that confused me for a while too. I apparently have multiple problems. I discovered that the bulkhead connector from my new engine harness was not fully seated in the fuse block. Looked like it was crocked. Took it out and made sure it went it straight and was tight. That fixed the BU light problem and all the intermittent dash problems. Unfortunately, I think the Tach got smoked along the way as the needle is pegged. The dome light goes out too (after the time delay). Still need to fix the horn as it blows all the time. Getting closer.