TerryD

s4 t2
The alternator charges which is good, if you unplug the connector in the back, it still charges, shouldn't the alternator not charge with it unplug? also WOT in boost, voltage drops down near 13.0v

Hot_Dog

The alternator output voltage should be 14.1 to 14.7 volts when measured between the "B" terminal and alternator case. Also, the voltage drop measured across the battery terminals should be within 0.1 volt of the alternator voltage at terminal "B". The Mazda FSM says do not start the engine while the plug is disconnected. I think that running the engine with plug disconnected would cause the alternator to become unstable and output an excessively high voltage.