B1785

DTC B1785

CIRCUIT DESCRIPTION
Battery positive voltage is supplied to the rear seat module (RSM) from a 30-amp fuse located in the rear fuse block. When commanded, this voltage is used by the RSM to power the seat motors through there respective motor control circuits. During seat operations, the driven motor current is monitored through the motor control circuits by the RSM. When an overcurrent condition is detected, the RSM disables the seat motors in order to protect the internal RSM circuitry.

DTC DESCRIPTORs
This diagnostic procedure supports the following DTCs:
- DTC B1547 Seat Back Rotation Motor Circuit
- DTC B1770 Seat Motor 2 (Assembly Horizontally) Circuit
- DTC B1785 Seat Motor (Recline) Circuit

CONDITIONS FOR RUNNING THE DTC
The RSM monitors for overcurrent only when the seat motors are active.

CONDITIONS FOR SETTING THE DTC
The RSM will set this DTC when the measured current exceeds 81 amps for 100 milliseconds.

ACTION TAKEN WHEN THE DTC SETS
- If the seat is moving when this condition occurs, the operation will be aborted.
- The RSM will not respond to all third row seat switch inputs.
- The RSM will set a history DTC.

CONDITIONS FOR CLEARING THE DTC
- The RSM does not detect an overcurrent condition during seat movement.
- The history code will clear if the RSM does not detect an overcurrent for 100 ignition cycles.

TEST DESCRIPTION

Steps 1 - 9:

The numbers below refer to the step numbers on the diagnostic table.
2. This test determines which directional motor exhibits excessive current.
3. This test determines if the suspect motor has an internal short to ground.
9. This test verifies the repair.