P0840

R1: CHECK THE CONTINUITY OF THE REVERSE SWITCH CIRCUIT INPUT SIGNAL FAILED
1. Raise and support the vehicle.
2. Disconnect the PCM electrical connector GB1.
3. Disconnect the transmission vehicle harness connector GB5.
4. Measure the resistance between the PCM electrical connector GB1 pin 30, (WU) and the transmission vehicle harness connector GB5 pin 13, (WU).
-> Yes
Goto [R2]
-> No
REPAIR the circuit between the PCM electrical connector GB1 pin 30, (WU) and the transmission vehicle harness connector GB5 pin 13, (WU). CLEAR DTC. TEST the system for normal operation.

R2:
1. Measure the resistance between the transmission vehicle harness connector GB5 pin 13, (WU) and GROUND.
^ Is the resistance less than 0.5 Ohms?
-> Yes
REPAIR the circuit between the PCM electrical connector GB1 pin 30, (WU) and the transmission vehicle harness connector GB5 pin 13, (WU). CLEAR DTC. TEST the system for normal operation.
-> No
INSTALL a new PCM. CLEAR DTC. TEST the system for normal operation.