P0797

DTC P0797 PRESSURE CONTROL SOLENOID VALVE C STUCK ON
Description





- This malfunction will not be detected while the A/T CHECK indicator lamp is indicating another self-diagnosis malfunction.
- This is not caused by electrical malfunction (circuits open or shorted) but by mechanical malfunction such as control valve sticking. improper solenoid valve operation. etc.
- The pressure control solenoid valve C is normally low, 3-port linear pressure control solenoid.
- The pressure control solenoid valve C is activated to control the apply and release of the 2nd brake and 1st and reverse brake, and torque converter clutch.
- Lock-up operation, however, is prohibited when A/T fluid temperature is too low.
- When the accelerator pedal is depressed (less than 1/8) in lockup condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.

On Board Diagnosis Logic
- This is an OBD-II self-diagnostic item.
- Diagnostic trouble code "PC SOL C STC ON" with CONSULT-II or P0797 without CONSULT-II is detected when condition of pressure control solenoid valve C is different from monitor value, and relation between gear position and actual gear ratio or lock-up status is irregular.

Possible Cause
- Pressure control solenoid valve C (On stick.)
- Hydraulic control circuit

DTC Confirmation Procedure

NOTE: If "DTC Confirmation Procedure" has been previously performed, always turn ignition switch "OFF" and wait at least 10 seconds before performing the next test.

After the repair, perform the procedure to confirm the malfunction is eliminated.

WITH CONSULT-II





1. Turn ignition switch "ON". (Do not start engine.)
2. Select "A/T" with "DATA MONITOR" mode in CONSULT-II.
3. Start engine.
4. Run engine for at least 4 consecutive minutes at idle speed.
5. If DTC is detected, go to AT-577, "Diagnostic Procedure".

WITH GST
Follow the procedure "With CONSULT-II".

Wiring Diagram-AT-PC/CS

AT-PC/CS-01:

AT-PC/CS-01

Diagnostic Procedure
1. CHECK PRESSURE CONTROL SOLENOID VALVE C SIGNAL

With CONSULT-II
1. After warming up the engine and transaxle, turn ignition switch "OFF".
2. Turn ignition switch "ON". (Do not start engine.)
3. Select "A/T" with "DATA MONITOR" mode in CONSULT-II.








4. Read out the value of "PC SOL C OUT" and "PC SOL C MON".

Without CONSULT-II
1. Start the engine.








2. Check pulse between TCM connector terminals 28 and 45.
OK or NG
OK >> GO TO 7.
NG >> GO TO 2.

2. CHECK PRESSURE CONTROL SOLENOID VALVE C CIRCUIT
1. Turn ignition switch "OFF".
2. Disconnect the TCM connector.








3. Check resistance between TCM connector terminals 28 and 45.
OK or NG
OK >> GO TO 7.
NG >> GO TO 3.

3. CHECK TERMINAL CORD ASSEMBLY WITH PRESSURE CONTROL SOLENOID VALVE C
1. Turn ignition switch "OFF".
2. Disconnect terminal cord assembly harness connector.








3. Check resistance between terminals 2 and 5.
OK or NG
OK >> GO TO 4.
NG >> GO TO 5.

4. CHECK HARNESS BETWEEN TCM AND TERMINAL CORD ASSEMBLY
Check the following.
- Open or short-circuit in the harness between TCM and terminal cord assembly.
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.

5. CHECK PRESSURE CONTROL SOLENOID VALVE C
1. Remove side cover. Refer to "Side cover".
2. Disconnect pressure control solenoid valve C harness connector.








3. Check resistance between terminals 1 and 2.
OK or NG
OK >> GO TO 6.
NG >> Replace the control valve assembly. Refer to "Control Valve Assembly".

6. CHECK HARNESS BETWEEN TERMINAL CORD ASSEMBLY AND PRESSURE CONTROL SOLENOID VALVE C
Check the following.
- Open or short-circuit in the harness between terminal cord assembly and pressure control solenoid valve C.
OK or NG
OK >> GO TO 7.
NG >> Repair or replace transmission wire. Refer to "Terminal Cord Assembly".

7. CHECK TCM
1. Check TCM input/output signal. Refer to "TCM Input/Output Signal Reference Values".
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> GO TO 8.
NG >> Repair or replace damaged parts.

8. CHECK DTC
Perform "DTC Confirmation Procedure". Refer to "DTC Confirmation Procedure".
OK or NG
OK >> INSPECTION END
NG >> Replace the control valve assembly. Refer to "Control Valve Assembly".

Component Inspection
PRESSURE CONTROL SOLENOID VALVE C
1. Remove side cover. Refer to "Side cover".
2. Disconnect pressure control solenoid valve C harness connector.








3. Check resistance between terminals 1 and 2.
4. If NG, replace the control valve assembly. Refer to "Control Valve Assembly".