[aMaizedGoat]

I have never had a problem starting my car until recently. When I turned the key a few weeks ago, the motor spun one time the the starter solenoid started clicking. I figured dead battery. After a normal charge, tried again, same results. I borrowed another battery and the car started. A week later went to start the car and I have what again seems to be a dead battery? Charged the battery at 2A for a week, just tried to start the car, motor wont turn, solenoid barely clicks.
I have 12.7V at the battery, but my voltmeter in the car reads 10.2V?
What could be going on here? I'm confused?

[67cruiser]

voltage regulator???

[BVR421]

My best guess based on experience is likely a thin film of corrosion under the clamps on the battery posts if it is happening this time of year. (cold damp nights)

If the battery is good and 12+v at rest sounds good, either the positive or the negative cable is not making good contact. Positive is most often the offender for corrosion but either could simply be loose or dirty on battery, starter or ground.

You could suspect the starter and or solinoid but the 10v -in- the car means a bad connection somewhere.

This is assuming cables and clamps in very good condition. If your cables, clamps and battery posts are not clean and dry inside and out then the problem is obvious.

Sometimes not so obvious is what you cant see between cable clamp and battery post. Fix-it clamps an the end of battery cables can be a real problem too.

[2002Z4CSS]

Possible high resistance in the batter cables or a bad connection.