P0771

DTC P0771 Shift Solenoid E Performance (Shift Solenoid Valve SR)

SYSTEM DESCRIPTION





The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body or automatic transaxle (clutch, brake or gear etc.).

MONITOR DESCRIPTION
The ECM commands gear shifts by turning the shift solenoid valves ON/OFF. According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual gear position (1st, 2nd, 3rd, 4th or 5th gear position). When the gear position commanded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL and stores the DTC.

Monitor Strategy:

Typical Enabling Conditions - Part 1:

Typical Enabling Conditions - Part 2:

Typical Malfunction Thresholds








HINT: Performing the ACTIVE TEST using the intelligent tester allows the relay, VSV, actuator and so on to operate without parts removal. Performing the ACTIVE TEST as the first step of troubleshooting is one method to shorten labor time. It is possible to display the DATA LIST during the ACTIVE TEST

1. PERFORM ACTIVE TEST
a. Warm up the engine.
b. Turn the ignition switch off.
c. Connect the intelligent tester to the DLC3.
d. Turn the ignition switch to the on position.
e. Turn on the tester.
f. Select the item DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST SHIFT.
g. According to the display on the tester, perform the ACTIVE TEST.





HINT: While driving, the shift position can be forcibly changed with the intelligent tester. Comparing the shift position commanded by the ACTIVE TEST with the actual shift position enables you to confirm the problem.

HINT:
- This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
- The shift position commanded by the ECM is shown in the DATA LIST/SHIFT display on the intelligent tester.

INSPECTION PROCEDURES

Step 1:

Steps 1(continued)-4: