Charging problem??
Thread Starter
8th Gear
Joined: Sep 2012
Posts: 8
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Charging problem??
So,, I'm 8 hrs from home and its 40 c out,,air conditioning is cranked and we are barely moving for 20 min and I look down and the volts are at 12.4 I turn off the air and hit highway speed and it only goes up to 12.9 volts,, I pulled into the hotel and let the engine cool for two hours ( the alt. was real hot as was the rest of the engine comp.),, I started the engine and the volts went right down to about 8 and slowly climbed to 12.6 and did not change if I revved it up. It drove for around an hour after I first noticed it was low but didn't seem to get any worse than the 12.9 even with he air on. I flipped on the lights and it went up to 13.3 but went back to 12.8 after a while. At the start of the trip it was over 14. Any advice before I head out in the morning to buy tools and parts.
Safety Car
Joined: Jul 2012
Posts: 4,558
Likes: 285
From: Houston Texas
C5 COTM Coordinator
So,, I'm 8 hrs from home and its 40 c out,,air conditioning is cranked and we are barely moving for 20 min and I look down and the volts are at 12.4 I turn off the air and hit highway speed and it only goes up to 12.9 volts,, I pulled into the hotel and let the engine cool for two hours ( the alt. was real hot as was the rest of the engine comp.),, I started the engine and the volts went right down to about 8 and slowly climbed to 12.6 and did not change if I revved it up. It drove for around an hour after I first noticed it was low but didn't seem to get any worse than the 12.9 even with he air on. I flipped on the lights and it went up to 13.3 but went back to 12.8 after a while. At the start of the trip it was over 14. Any advice before I head out in the morning to buy tools and parts.
Turns out the alternator's regulator had gone bad. Are you getting the "charge system fault" on the DIC?
Post up some codes if you can.
Thread Starter
8th Gear
Joined: Sep 2012
Posts: 8
Likes: 0
My check engine light is all that's on because I just had a lLS3 put in it with the throttle body off a LS2 and the fuel mixture is a bit off until it hits the Dino on Monday. I just did the solder repair yesterday on the brake controller so there will be lots of codes in it until Monday but no more lights came on in the dash besides the original check engine which was already on. There is also nothing scrolling across the dic either
Last edited by econway; Jul 26, 2013 at 12:21 AM.
Team Owner
Joined: Jul 2006
Posts: 22,141
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From: Kannapolis NC
If it were mine, I'd have an auto parts store test the alternator and battery. I'd also check the connection on the red wire to the starter from the battery. That's where the voltage from the alternator ties to the battery connection. But that's just me.
Le Mans Master
Joined: Mar 2004
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From: Ft. Lauderdale Fl
Your dead on.
Race Director
Joined: Apr 2007
Posts: 11,150
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From: South Western Ontario
You may have a connection problem. Check the connections at the starter solenoid and check the connections at the battery. You should also check the negative cable where it connects to the engine block.
Take a volt meter and measure voltage at the post on the back of the alternator and at the positive battery post. both should be very close to equal.
No, you never want to do that test on a vehicle with electronics in it.
Take a volt meter and measure voltage at the post on the back of the alternator and at the positive battery post. both should be very close to equal.
No, you never want to do that test on a vehicle with electronics in it.
