77 electrical issues

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Feb 14, 2014 | 10:18 AM

Vivian1127

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77 electrical issues

My 77 suddenly failed to turn on one day when I tried to take her out. I am getting no power to any dash instruments and no starter clicking.

I have checked the battery and I am getting 12 volts on the voltmeter. I am getting 12 volts at the starter as well.

I removed the ground connection underneath the car and inspected and cleaned it. Still no power.

My headlights will still cut on which I thought was interesting.

I am starting to wonder if it is some fuse that has blown. Since I am getting no power anywhere, I am thinking it is something besides the ignition system but correct me if I am wrong.

Interesting thing to note if it helps diagnose the issue, earlier in the day when I was driving her, the radio would cut out and then cut back on and the light in the roof of the car would turn on randomly and get really bright.

Thanks in advance for your thoughts and suggestions.

Feb 14, 2014 | 11:55 AM

MelWff

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An exact 12V reading is probably a dead battery, minimum 12.5V to start. What does the voltage reading drop to when you turn the key to engage the starter? Did you connect a battery charger for a couple of hours and recheck the reading when trying to start? Did you recheck the tightness of the battery connections?

Last edited by MelWff; Feb 14, 2014 at 11:58 AM.

Feb 14, 2014 | 12:21 PM

Vivian1127

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Quote:

Originally Posted by MelWff

The battery is brand new bought just 3 months ago. It is not exactly 12 volts, i think it got up to 12.4v which should be enough to at least get some instruments to light up that I am not currently getting.

I have tried to jump start the battery to get some life in the car with no luck.

I have checked and rechecked battery connections with no luck.

Feb 14, 2014 | 03:29 PM

MelWff

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Have you checked the connection at the starter? Have you checked the fusible link? Three month old batteries can loose charge from a bad alternator or a defect or a drain. Can you check voltage at the starter with somone turning the key?

Feb 14, 2014 | 06:32 PM

DUB

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Quote:

Originally Posted by MelWff

If your headlights are working...I would bet that your brake lights would work also. IF not...and the fusible link is good....then it is time to check the power at your ignition switch on top of your steering column and see what is going on there.

DUB

Feb 15, 2014 | 01:11 AM

'02magredZ51

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From: Florida

Not to poke the bear... but we had an interior light problem on a '77 I helped rebuild. When we pulled the dash and console and to trace the wires we found the entire dash harness had melted together in a couple places. Strangely enough most things still worked. Worth a thorough check with a bright flashlight and a mirror.

Good luck.

Feb 17, 2014 | 07:45 PM

Vivian1127

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Update- all is well now! Turns out it was the fusible link.

I replaced the fusible link a few months ago when my starter went out and I guess I gave the link a bad crimp job. I replaced the crimp and she started right up!

I appreciate all the suggestions that everyone provided.