B410

Schematic:

DESCRIPTION
The generator on this vehicle has fault detection capability built into the regulator. The Body Control Module (BCM) will supply 12 volts to the regulator over CKT 225, the I-terminal, and monitor the field voltage of the generator by way of a Pulse Width Modulated (PWD) signal over CKT 23, the F+ terminal.


Code B410 will set if there is an open or short to ground in either CKT 23 or CKT 225, a drive belt break or if an undervoltage or overvoltage condition exists. If there is a short to ground on CKT 225, the "NO CHARGE" telltale will light on the Instrument Panel Cluster (IPC).

TEST DESCRIPTION
The numbers below refer to circled numbers on the diagnostic chart:
1. BCM input B151 displays generator signal voltage as HI or LO depending on the voltage state at the BCM. Normally with key on, engine off, CKT 225 will be pulled LO by the generator and B151 will read LO.
2. This step checks to see if the LO readings due to CKT 225 or the generator. If the reading changes from LO to HI when the generator is disconnected, then CKT 225 and the BCM are okay.
3. This step determines if the fault is due to the BCM or CKT 225.
4. BCM data value BD51 displays the amount of generator field activity. Under normal conditions, a reading below 7% would indicate a fault in the field circuit or the BCM.
5. Removing the generator connector will determine if the fault is due to the generator or an open in CKT 225, including the BCM and interface connector.

NOTE ON INTERMITTENTS
If an intermittent condition exists, perform the battery and charging system checks. Perform a comprehensive visual check of the generator wiring and connections.