Test B: One Low Beam Headlamp Is Inoperative

PINPOINT TEST B: ONE LOW BEAM HEADLAMP IS INOPERATIVE

B1-B2:

B2-B4:

B4-B5:

Normal Operation
The smart junction box (SJB) receives voltage from the battery junction box (BJB) through circuits SBB34 (YE/RD) (LH headlamp) and SBB29 (GY/RD) (RH headlamp). When the SJB detects the headlamp switch in the HEADLAMPS ON position and the multifunction switch in the LOW BEAM position, the SJB sends voltage through circuits CLF04 (BN/BU or GN/OG) (LH headlamp) and CLF05 (BU/GN or GN/OG) (RH headlamp) to the low beam headlamps. Ground is supplied on circuits GD120 (BK/GN or BK) (LH headlamp) and GD123 (BK/GY or BK) (RH headlamp).

DTC B1795 - is a continuous and on-demand DTC that sets when the SJB detects an open from the LH or RH low beam voltage supply circuit.

DTC B1797 - is a continuous and on-demand DTC that sets when the SJB detects a short to ground from the LH or RH low beam voltage supply circuit. The self-test must be run after the repair in order for the SJB to enable the output for the low beam voltage supply.

DTC B2501 - is a continuous and on-demand DTC that sets when the SJB detects an open from the LH low beam voltage supply circuit.

DTC B2503 - is a continuous and on-demand DTC that sets when the SJB detects an open from the RH low beam voltage supply circuit.

Possible Causes
- Fuse
- Circuit CLF04 (BN/BU or GN/OG) open or short to ground
- Circuit CLF05 (BU/GN or GN/OG) open or short to ground
- Circuit GD120 (BK/GN or BK) open
- Circuit GD123 (BK/GY or BK) open
- Circuit SBB29 (GY/RD) open
- Circuit SBB34 (YE/RD) open
- SJB