B411

BCM Code B411 Or Code B412:

Battery Voltage Circuit:

CIRCUIT DESCRIPTION:
Code B411 will set when the ignition is "ON" and the engine RPM is greater than 800 and the BCM is seeing an Ignition-1 reference voltage of less than 10 volts for more than 50 seconds. The message "BATTERY VOLTS LOW" will be displayed on the CCDIC. Code B412 will be set if the voltage is over 16 volts for more than 50 seconds. The message "BATTERY VOLTS HIGH" will be displayed on the CCDIC.

TEST DESCRIPTION: Test numbers refer to circled numbers on the diagnostic chart.

1. If the PCM and BCM are not "seeing" the same battery voltage, then the BCM voltage supply and ground are suspect.
2. If the PCM and BCM voltage parameters are within 1 volt, refer to generator diagnosis.

NOTES ON INTERMITTENTS:
If an intermittent Code B411 or B412 is being set, observe BCM data value BD50. This battery voltage reading is monitored off of the 10A ISC IGN-1 fuse, fuel reference voltage PIN "3D1."