Ammeter pegs out
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From: Piedmont Missouri
Ammeter pegs out
Does anybody know why my ammeter on my 69 would peg out on the + side when at normal driving rpm's? When the engine is idling it reads just to the right of center. But when I give it gas, it moves quickly right then pegs out. If I let off of the gas it goes back to just right of center. I know the alternator is internally regulated on a 69, right? So what other options could cause this? Thanks for the help.
Mark
Mark
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From: charlotte north carolina
It seems like you are forcing all the alternator output thru the ammeter circuit, instead of the #10 red wire that goes from the horn relay to the starter solenoid. Check the connections at both ends, and also the fusible link in that circuit. If you continue to drive the car in this condition, you may fry the ammeter.
Thread Starter
Instructor
Joined: Nov 2013
Posts: 249
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From: Piedmont Missouri
It seems like you are forcing all the alternator output thru the ammeter circuit, instead of the #10 red wire that goes from the horn relay to the starter solenoid. Check the connections at both ends, and also the fusible link in that circuit. If you continue to drive the car in this condition, you may fry the ammeter.
Thanks, I'm going to try to trace the wires down tonight.
Thread Starter
Instructor
Joined: Nov 2013
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From: Piedmont Missouri
I traced these wires down and everything looks ok. Is there a way to test the horn relay to make sure there is not a short there? I know the key buzzer doesn't work and I think it's in the same relay. I tested battery voltage tonight and had about about 12 on the battery with the car off. After I start it with it idling I have around 15 and if I give it gas I have about 20. So it's definitely overcharging. I'm just not that great at the electrical stuff and don't know where to start. Thanks for any help.
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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Kiss !
Sounds like the voltage regulator inside the alternator is bad.
Have it tested before you cook the battery.
Have it tested before you cook the battery.
Thread Starter
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From: Piedmont Missouri
