Battery Tester's Elusive Fluctuations Decoding Signals While Driving

The voltage regulator shuts down the alternator as the battery reaches its charge and the gauge gradually drops to battery voltage. When there's ... drops to 12.5 while driving ... If it keeps up, then have a FLAPS load test the battery no alternator at RPM you are seeing the fluctuations. The voltage at the battery should not drop below 12 volts engine off for a healthy battery, and not go above 14.5 when running. You may have a battery or ... No it will NOT immediately go to 14 volts while the grid heaters are cycling...they pull a huge amount of current, more than the alternator can ... First, check the battery clamps themselves. Have they been over tightened over the years so they are distorted and cannot tightly grip the ... 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 sounds like the voltage regulator inside the alternator is bad. Just an FYI most all auto parts stores will test your alternator, battery, ... 1v while the truck is running, the crossover cable is not allowing the drivers side battery to charge at the same rate. 2005 QCSB, cold air ... It's likely your charger. Sometimes they get a little loose in the socket and they might vibrate out, or the charger needs the contact points ... Remove the ECU 32 pin wiring harness connectors and inspect the clips and pins for oxidation. The ECU controls the alternator charging rate of ...