Test F: The Charging System Warning Indicator Flickers or Is Intermittent
PINPOINT TEST F: THE CHARGING SYSTEM WARNING INDICATOR FLICKERS OR IS INTERMITTENTF1-F3:
F3 Continued:
Normal Operation
With the engine running, the charging system warning indicator is off. The A (battery sense) circuit 35 (OG/LB) to the generator field coil measures 13-15 volts. The S (stator) circuit (internal to the generator on all 4.6L vehicles but an external circuit 4 [WH/BK] on 4.0L vehicles) is used to feed back a voltage signal from the generator to the voltage regulator. This voltage feedback signal (typically half the battery voltage) is used by the regulator to provide a signal to the PCM which in turn provides a signal over the controller area network (CAN) communication link to the instrument cluster to turn off the charging system warning indicator. The I (ignition) circuit 904 (LG/RD) is used to turn on the voltage regulator. This circuit measures 6-8 volts (C102a connected) with the ignition switch in the ON position and the engine not running. Once the engine is started, the I circuit measures 8-10 volts (C102a connected). The battery positive output (B+) circuit 38 (BK/OG) is the generator output supplied to the battery and electrical system.
Possible Causes
- battery junction box (BJB) fusible links 290A 12 ga (GY), 290B 12 ga (GY) or 292C 18 ga (BN) intermittently open
- external S circuit 4 (WH/BK) (if equipped) open or high resistance
- generator connections
- generator