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Home >> Mercury >> 2005 >> Mountaineer 2WD V8-4.6L SOHC VIN W >> Repair and Diagnosis >> Starting and Charging >> Charging System >> Testing and Inspection >> Pinpoint Tests >> Test A: The Battery Is Discharged or Battery Voltage Is Low

Test A: The Battery Is Discharged or Battery Voltage Is Low

PINPOINT TEST A: THE BATTERY IS DISCHARGED OR BATTERY VOLTAGE IS LOW


A1-A4:






A4-A5:






Normal Operation
The generator output is supplied through the battery positive output (B+) circuit 38 (BK/OG) terminal on the rear of the generator to the battery and electrical system. During normal operation the charging system warning indicator is off with the ignition switch in the ON position and the engine running. The charging system warning indicator is on with the ignition switch in the ON position and the engine off.

Possible Causes
- generator B+ circuit 38 (BK/OG) high resistance
- positive battery cable high resistance
- negative battery cable high resistance
- high ignition switch-off current drain(s)
- battery
- generator

CAUTION:
- Do not make jumper connections except as directed. Incorrect connections may damage the voltage regulator test terminals, fuses or fusible links.
- Do not allow any metal object to come in contact with the generator housing and internal diode cooling fins. A short circuit may result and burn out the diodes.


NOTE:
- While carrying out any pinpoint test, disregard any DTCs set while following any specific pinpoint test. After the completion of any test, be sure to clear all DTCs.
- All voltage measurements are referenced to the negative (-) battery post unless otherwise specified.
- When the battery has been disconnected and reconnected, some abnormal drive symptoms may occur while the PCM relearns its fuel trim. The vehicle may need to be driven to relearn the strategy.