Fluctuating Voltage
Thread Starter
Instructor
Joined: Sep 2000
Posts: 147
Likes: 0
From: Erial NJ
Cruise-In VII Veteran
Fluctuating Voltage
Yesterday, while sitting at a light, I noticed the clock flickering. This prompted me to set the DIC to battery voltage. The voltage continuously changed between 12.9 and 13.6 volts, whether the engine was idleing or at 1600 RPM while driving on the highway. I don't recall any time in which it stayed the same value for more than a second.
I have 2 questions: What is the normal voltage according to the DIC and is the fluctuation normal?
The air-conditioner and radio were on, but nothing else.
Thanks,
Raymond
I have 2 questions: What is the normal voltage according to the DIC and is the fluctuation normal?
The air-conditioner and radio were on, but nothing else.
Thanks,
Raymond
Burning Brakes
Joined: May 2001
Posts: 918
Likes: 1
From: New Orleans, LA
Re: Fluctuating Voltage (NassauBlue)
At times, mine will fluctuate rapidly between 13.9 and 13.8, but I've never seen as wide a fluctuation as you described. Of course, sometimes when the cooling fan kicks on, it will drop down to 12.9 for a second, but it comes back up right away.
Safety Car
Joined: Oct 2000
Posts: 3,654
Likes: 0
From: Downtown Chicago IL
Re: Fluctuating Voltage (NassauBlue)
uh-oh. Mine had the same symptoms....it's been at the dealer since last Friday and they haven't found a thing. Did the car throw any codes? I pick up the car today from the dealer and to my knowledge they haven;t found a single problem. These electrical gremlins are scary....hope you get it figured out.
Le Mans Master
Joined: Dec 2000
Posts: 5,348
Likes: 3,317
Re: Fluctuating Voltage (O-Ace)
I had a similar problem but the first symptom was that my car would not start. All lights, radio, etc. were fine. Even when jumped,
the starter would just "click..click..click". I was able to push start my car and get to a dealer. I assumed the starter was dead. During the trip to the dealer the battery voltage read between 12.0 and 13.5 or so. Normally I see 13.8 to 14.2 or so.
The dealer also initially suspected the starter. Ten minutes later however, the mechanic came back and said it was loose battery connections. Simple fix.
I imagine that the loose connections allowed enough current through to run the electronics and computers, but would not allow sufficient amperage through to engage the starter.
I hope your issue is as simple.
the starter would just "click..click..click". I was able to push start my car and get to a dealer. I assumed the starter was dead. During the trip to the dealer the battery voltage read between 12.0 and 13.5 or so. Normally I see 13.8 to 14.2 or so.
The dealer also initially suspected the starter. Ten minutes later however, the mechanic came back and said it was loose battery connections. Simple fix.
I imagine that the loose connections allowed enough current through to run the electronics and computers, but would not allow sufficient amperage through to engage the starter.
I hope your issue is as simple.
Thread Starter
Instructor
Joined: Sep 2000
Posts: 147
Likes: 0
From: Erial NJ
Cruise-In VII Veteran
Re: Fluctuating Voltage (Elk)
Elk,
Looks like you hit the nail on the head. Thanks. Both of my battery cables were loose. They weren't loose enough to cause any starting problems, though. I tightened the cables and the voltage is now staying steady at 12.9. That still seems low, but I've never seen 14's with this car, and I've never had a dead battery.
O-Ace - Maybe your battery cables are loose (or corroded) too?
Looks like you hit the nail on the head. Thanks. Both of my battery cables were loose. They weren't loose enough to cause any starting problems, though. I tightened the cables and the voltage is now staying steady at 12.9. That still seems low, but I've never seen 14's with this car, and I've never had a dead battery.
O-Ace - Maybe your battery cables are loose (or corroded) too?
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