C5 '98 A4, erratic voltage
Thread Starter
Instructor
Joined: Nov 2004
Posts: 113
Likes: 2
C5 '98 A4, erratic voltage
I have a '98 A4. No mods. There are no codes at this time. Some days the voltage jumps between 13.5 and 14.1, during highway driving I see constant fluctuations in voltage, it keeps changing every second. The lights on the radio and AC are flickering. I suspect that this is not not normal, I refuse to imagine that this is healthy for all the electronic equipment in this car. On some days the voltage stays constant and there are no flickering lights. The fluctuations seem to be getting more severe - today the voltage was floating in a wider range, 12.9 to 14. I have an AC delco battery that is a couple of years old.
My suspicions are:
1. Bad contact - battery wiring.
2. Bad contact - alternator.
3. Bad alternaror (voltage regulator?)
4. Bad battery
Any experiences with jumping voltage?
My suspicions are:
1. Bad contact - battery wiring.
2. Bad contact - alternator.
3. Bad alternaror (voltage regulator?)
4. Bad battery
Any experiences with jumping voltage?
Racer
Joined: Apr 2006
Posts: 386
Likes: 0
From: Wichita Kansas
If you don't find loose terminals or corrosion at the battery then you probably have a bad ground somewhere. Check the sticky (Important Electrical Information) at the top of the C5 Tech Community.
Dave
Dave
Le Mans Master
Joined: Jul 2004
Posts: 7,727
Likes: 7
From: Twilight zone
St. Jude Donor '05-'06
Originally Posted by juha_teuvonnen
It was oxidized positive battery terminal. Just washed it with little baking soda and the problem went away.
Glad it was an easy fix this time
