Contour Enthusiasts Group Archives Forums General Troubleshooting Surging Voltage

'Sup all;

Weird issues abound. When I turn on my E0, the volts spike up and down, going from about 9 to 15. Just up and down, with the lights dimming and the battery light flicking on and off. When I drive the car, the volts read at 14, and stay there. Stop at a light, back to the spikey-thang. A new alternator is going in soon, anyway, but could this be something else? I assume we don't have an external voltage regulator or anything.... Oh, the battery is about 1.5 years old.

Thanks!

This sort of thing is usually a battery problem. Likely a flakey internal connection that is temperature and voltage sensitive. If you can, try substituting a known good battery and see what happens.

I'd say a battery would be a good investment at this point... I mean, the thing's only got to go 12 miles or so to John's house, so it could probably make it entirely on a new battery.

It's amazing how much stuff gets easier to replace when the whole trans is out. As always, thanks Jim.

So I replaced the battery; now it surges up and down for a minute, then stays at 11v with the battery light fading in. Sounds like a dying alternator to me! Anything else I should look into?

A brand new battery should not do that, even if there is an alternator problem. It sounds like the new battery is low on charge. You cannot properly test a charging system without first qualifying the battery.

Put the battery on a trickle charger overnight.
You can then have the battery load tested at a reputable parts store for free.
It that is a go and the problem still persists, it could be the voltage regulator or diodes in the alternator. That can be tested as well with it out of the car.