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'67 instrument cluster problems

1670 Views 13 Replies 7 Participants Last post by  Flade
I pulled the cluster on my 67 coupe to replace the non-functioning bulbs with LED's. Now I still have no lights (other than the Brake light). Following advice elsewhere I replaced the ignition switch and the constant voltage regulator with no help. I have no power to three of the fuses and I suspect this may be at least part of the problem. How do I remedy this??

Thanks in advance
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Using a wiring diagram, trace where power is introduced to the circuit for each "dead" fuses. Trace back and find where the power stops.

50 year old harnesses are not happy harnesses.

You need the diagram.
 

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First and foremost never shotgun parts at a problem. You've added variables that didn't need to be added. To you own a test light or volt meter? What three fuses don't have power?
 

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The constant voltage regulator doesn't do anything with the dash lights. So you can rule that out. It just runs the gauges.
The fuses do affect the lights though, specifically the one in the middle labelled "Inst. L.T."

800725

Also, the fuse box connectors can get dirty and rusty over time so you might want to clean them off too. Disconnect the battery first just to make sure you don't short anything out while you're cleaning.

LEDs can be a little finicky. You might want to find one good old bulb and put it in while you're testing just to make sure you're not having a problem the LEDs. The LEDs dim differently than the old bulbs and they might not work at all if the headlight switch isn't rotated all the way to the left.

IIRC the power to the lights goes from the headlight switch to the fuse to the dash lights so it's possible that your headlight switch is bad, but definitely fix the fuses first.
 

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Discussion Starter · #9 ·
The constant voltage regulator doesn't do anything with the dash lights. So you can rule that out. It just runs the gauges.
The fuses do affect the lights though, specifically the one in the middle labelled "Inst. L.T."

View attachment 800725
Also, the fuse box connectors can get dirty and rusty over time so you might want to clean them off too. Disconnect the battery first just to make sure you don't short anything out while you're cleaning.

LEDs can be a little finicky. You might want to find one good old bulb and put it in while you're testing just to make sure you're not having a problem the LEDs. The LEDs dim differently than the old bulbs and they might not work at all if the headlight switch isn't rotated all the way to the left.

IIRC the power to the lights goes from the headlight switch to the fuse to the dash lights so it's possible that your headlight switch is bad, but definitely fix the fuses first.
I have NO power to the lights since the ONLY fuses with power are the 7.5 and 20 amp ones. I seem to have a vague recollection that the other fuses receive power from the ignition switch, but can't find the reference.
 

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Sounds like an issue with the headlight switch or wiring. Might want to consider sending your dash harness to Midlife for refurbishment.
 
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