Test J: DTC B2974 - Lighting Mode Switch Input Circuit Failure

PINPOINT TEST J: DTC B2974 - LIGHTING MODE SWITCH INPUT CIRCUIT FAILURE

J1-J2:

J3-J4:

Normal Operation
The smart junction box (SJB) monitors the dimmer control switch status on circuit 1405 (LB/BK) to determine if the courtesy lamps are requested. Based on the dimmer control switch status, the SJB then energizes the interior lamp circuits.

Possible Causes
- Circuit 1405 (LB/BK) open or shorted to ground
- Dimmer control switch
- SJB