Battery Diagnostics On-the-Go Interpreting Fluctuating Tester Readings

I'll have to stop by Autozone and have them do a test on the alternator, I installed a brand new interstate battery about 7ish months ago give ... There is always the possibility that the battery is simply at its end of its useful life. Voltage readings of the battery and during charging ... Reason is, your charger might see it as a short (very high amperage load at the onset). Also, check terminal connections for corrosion or lose ... It's completely normal for voltage to fluctuate based on engine load. If the car needs more power (such as during acceleration), it may dial back the charging ... Does so at idle or while driving down the road. Tail lights ... I placed volt meter on the battery and showed him the voltage fluctuation. A good battery with engine off should read 12.5vdc. Your charging system (DIC) when running should read about 14.2vdc. When I start my car, my volt meter is showing a steady 13.8 volts. However, once the car heats up, or after 10 minutes driving, it drops to 11.9 ... It is highly likely that the alternator and/or voltage regulator are the problem. '04 330i ZHP - OEM Clears - ///M Strut bar - CoolantSnitch. This will cause the voltmeter to fluctuate between 12 and 14 volts as opposed to non-regulated systems that usually maintain a more consistent ... Especially around here in the cold, they can die without much warning. If the cables are crapped up, you can try cleaning all the terminals and ...