#1  
Old 10-07-2020, 09:20 AM
My64GTO My64GTO is offline
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Default Battery Light stays ON when car is OFF

I had a weird issue over the weekend. I took my '64 out for a ride and stopped at the parts store. As soon as I turned the car OFF to go inside, the battery light came on, and stayed on. So, I started the car, shut it off again and the light went out.

After leaving the parts store, I drove home, parked the car in the garage, shut the car off and the battery light stayed on again. I disconnected the battery, and reconnected it, and the light stayed off.

I didn't find much in the service manual about this. I haven't done much troubleshooting yet, but could it be the battery? The alternator? The regulator?

I have never had this happen before. It had been a while since I drove the car and the battery is old, but it still cranks the car over without a problem. All the harnesses are new as well.

  #2  
Old 10-07-2020, 03:59 PM
389 389 is offline
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Sounds like the key switch in the dash is going bad. Try to get a NOS GM ignition switch.. The 9 terminal has an extra terminal thats a switched ground to kill the AC when you start the car..

  #3  
Old 10-07-2020, 04:02 PM
My64GTO My64GTO is offline
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Thanks. It is a repop that I got about 5 years ago. I will try to find a NOS one, or at the very least another repop

Quote:
Originally Posted by 389 View Post
Sounds like the key switch in the dash is going bad. Try to get a NOS GM ignition switch.. The 9 terminal has an extra terminal thats a switched ground to kill the AC when you start the car..

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Old 10-07-2020, 04:11 PM
389 389 is offline
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I think it could also be a bad rectifier in the alt.

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Old 10-07-2020, 05:22 PM
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Stuart Stuart is offline
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I had it happen before, one of the diodes in the alternator failed. Check the battery voltage - if it goes up more than 14.5 volts or so when the engine is revved that's probably the problem.

  #6  
Old 10-07-2020, 05:35 PM
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steve v steve v is offline
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Check the regulator too, I've seen them cause that problem before.

  #7  
Old 10-07-2020, 07:12 PM
"QUICK-SILVER" "QUICK-SILVER" is offline
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Quote:
Originally Posted by steve v View Post
Check the regulator too, I've seen them cause that problem before.
Does sound like a sticky mechanical regulator.

Should listen for a click when he takes the battery cable off.

  #8  
Old 10-08-2020, 08:39 AM
My64GTO My64GTO is offline
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Thanks guys! I will check all these things this weekend and report back.

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