B409

Code B409 - Charging System Problem:

Wiring Diagram for Codes B409 & B410:

CODE B409 - CHARGING SYSTEM PROBLEM

Circuit Description:

The 17 SI generator has fault detection capability built into the regulator. The generator will pull CKT 225 LO if the regulator detects any of the following problems: open or shorted field circuit, drive belt break, overvoltage, and undervoltage conditions. CKT 225 will normally have 12v out of the BCM to the generator, in order to continously signal the regulator. A short to ground on CKT 225 will cause the generator to not work, as the 12v signal from the BCM never reaches the generator and a Code B409 will be set. An open in CKT 225 will set Code B410 only (see code chart B410). Code B409 will set, if the engine speed is greater than 600 RPM (Code B334 must not be set, otherwise the ECM cannot communicate engine speed to the BCM), and the BCM sees a LO.


Test Description:

1. BCM input B151 displays generator signal voltage as HI or LO depending on the voltage state at the BCM. Normally, with ignition on, engine off, CKT 225 will be pulled LO by the generator and B151 will read LO.

2. Check to see if the LO reading is due to the circuit or generator. If display reading changes from LO to HI when the generator is disconnected, with engine running, the BCM and wiring are OK.

3. Check to see if the LO reading is due to the BCM or the circuit. If display reading changes from LO to HI when BCM connector 3 is removed, the BCM is 0K.


Note on Intermittents:

If an intermittent code B409 is being set, manipulate CKT 225. When BCM input B151 change-of-state indicator displays an "x", the failure has been induced.