Retained Accessory Power Relays Circuit (Part 5 of 5)

Code B420 - Retained Accessory Power Relay Circuit (Part 5 of 5):

Wiring Diagram for Code B420 - Retained Accessory Power Relays Circuit:

CODE B420 - RETAINED ACCESSORY POWER RELAYS CIRCUIT

Circuit Description:

If the radio did not cycle on and off when B003 was selected, then, this is the system that set Code B420. RAP timeout is 10 minutes.


Test Description:

1. Checks to see if the fault is due to an open circuit or a short to ground in the circuit. If the radio is always on, then there is a short to ground in control circuit and if the radio never turns on, then there is an open in one of the circuits.

2. Checks to see if the short to ground is due to the circuit or the BCM.

3. Checks to see if the open circuit is due to the circuit or the BCM.

4. Checks to see if the open circuit is on the power or ground side of the relay.





Note on Intermittents:

If an intermittent Code B420 is being set, manipulate the related wiring in output function and watch for relays to cycle.