DTC P0801 Reverse Inhibit Control Circuit

WARNING: This page is about a different variant/trim than selected.

DTC DETECTING CONDITION:

Shift lock solenoid malfunction, open or short reverse inhibitor control circuit

TROUBLE SYMPTOM:

Gear is shifted from "N" range to "R" range during driving at 20 km/h (12 MPH) or more.
Gear cannot be shifted from "N" range to "R" range.

WIRING DIAGRAM:

Fig 1: Wiring Diagram - Reverse Inhibit Control Circuit

Courtesy of SUBARU OF AMERICA, INC.

DTC P0801 DIAGNOSTIC PROCEDURE

Step	CHECK	Yes	No
1 CHECK HARNESS CONNECTOR BETWEEN TCM AND SHIFT LOCK SOLENOID. Turn the ignition switch to OFF. Disconnect the connector from TCM and shift lock solenoid. Measure the resistance of harness between TCM and shift lock solenoid connector. Connector & terminal (B55) No. 18 - (B116) No. 3:	Is the resistance less than 1 Ω?	Go to step 2 .	Repair the open circuit in harness between TCM and shift lock solenoid connector.
2 CHECK HARNESS CONNECTOR BETWEEN TCM AND SHIFT LOCK SOLENOID. Measure the resistance of harness between TCM and chassis ground. Connector & terminal (B55) No. 18 - Chassis ground:	Is the resistance more than 1 MΩ?	Go to step 3 .	Repair the short circuit in harness between TCM and shift lock solenoid connector.
3 CHECK HARNESS BETWEEN SHIFT LOCK SOLENOID AND CHASSIS GROUND TERMINAL. Measure the resistance of harness between shift lock solenoid and chassis ground. Connector & terminal (B116) No. 4 - Chassis ground:	Is the resistance less than 1 Ω?	Go to step 4 .	Repair the open circuit in harness between chassis ground and shift lock solenoid connector.
4 CHECK SHIFT LOCK SOLENOID. Measure the resistance of shift lock solenoid terminals. Connector & terminal (B116) No. 3 - No. 4:	Is the resistance 12 - 18 Ω?	Go to step 5 .	Replace the shift lock solenoid.
5 CHECK OUTPUT SIGNAL FOR TCM. Connect all the connectors. Turn the ignition switch to ON. Shift the select lever to "D" range. Measure the voltage between TCM and chassis ground. Connector & terminal (B55) No. 18 (+) - Chassis ground (-):	Is the voltage more than 10.5 V?	Go to step 6 .	Go to step 7 .
6 CHECK OUTPUT SIGNAL FOR TCM. Lift-up the vehicle and support with rigid racks. NOTE: Raise all wheels off floor. Start the engine. Shift the select lever to "D" range and slowly increase vehicle speed to 20 km/h (12 MPH). NOTE: The speed difference between front and rear wheels may light the ABS warning light, but this indicates no malfunction. When AT control diagnosis is finished, perform the ABS memory clearance procedure of on-board diagnostics system. < Ref. to CLEAR MEMORY MODE . > Measure the voltage between TCM and chassis ground. Connector & terminal (B55) No. 18 (+) - Chassis ground (-):	Is the voltage less than 1 V?	Even if the SPORT indicator light is blinking, the circuit has returned to normal condition at this time. A temporary poor contact of connector or harness may be the cause. Repair the harness or connector in reverse inhibitor control circuit.	Go to step 7 .
7 CHECK POOR CONTACT.	Is there poor contact in the reverse inhibitor control circuit?	Repair the poor contact.	Replace the TCM. < Ref. to TRANSMISSION CONTROL MODULE (TCM) . >