Code B410, Charging System Circuit: Notes

The generator on this vehicle has fault detection capability built into the regulator. The BCM supplies 12 volts on circuit No. 25 and monitors the field voltage on circuit No. 23.

Code B410 will set if the following occur:

• An open or short to ground in circuits No. 23 or 25.
• Drive belt breakage.
• Overvoltage or undervoltage.

Circuit No. 25 will normally carry 12 volts from the BCM to the generator in order to continuously signal the regulator. A short to ground on circuit No. 25 will cause the generator to not work, a Code B409 to set, the "NO CHARGE" telltale will light on the IPC and the "GENERATOR PROBLEM" message will be displayed on the DIC.

1. BCM input BI51 displays generator signal voltage as "HIGH" or "LOW", depending on the voltage state at the BCM. Normally, with key on and engine off, circuit No. 25 voltage will be pulled low by the generator and BI51 will read "LOW".
2. Checks to see if "LOW" reading is due to circuit No. 25 or the generator. If display reading changes from "LOW" to "HIGH" when the generator is disconnected with engine running, the BCM and circuit No. 25.
3. Checks to see if the "LOW" reading is due to the BCM or circuit No. 25.
4. BCM data value BD51 displays the amount of generator field activity. Under normal conditions, a reading less than 7 percent would indicate a fault in the field circuit at the BCM.
5. Removing the generator connector will determine if the fault is due to the generator or an open in circuit No. 25, including the BCM and interface connector.