DTC P0768 [JA5A-EL]


BME050218901224

DTC P0768

Reduction timing solenoid valve circuit malfunction (open/short)

DETECTION CONDITION

• If there is open or short circuit in the reduction timing solenoid signal system (while the TCM monitors the solenoid output voltage, the voltage that differs from the ON/OFF signal output by the CPU in the TCM is detected), the TCM determines that there is a malfunction.
Diagnostic support note:
• This is continuous monitor (CCM).
• The MIL does not illuminate
• PENDING CODE is not available.
• FREEZE FRAME DATA is not available.
• The HOLD indicator light flashes.
• The DTC is stored in the TCM memory.

POSSIBLE CAUSE

• Open circuit in wiring harness between reduction timing solenoid valve terminal A and TCM terminal 2G
• Short to ground in wiring harness between reduction timing solenoid valve terminal A and TCM terminal 2G
• Short to power supply in wiring harness between reduction timing solenoid valve terminal A and TCM terminal 2G
• Reduction timing solenoid valve malfunction
• Damaged connector between reduction timing solenoid and TCM
• TCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related Service Bulletins and/or on-line repair information availability.
• Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
No
Go to the next step.
2
INSPECT TERMINAL COMPONENT NO.1 (12-PIN) FOR POOR CONNECTION
• Turn the ignition switch to the LOCK position.
• Disconnect the terminal component No.1 (12-pin).
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Are the terminals normal?
Yes
Go to the next step.
No
Repair or replace the terminals, then go to Step 12.
3
INSPECT RESISTANCE
• Inspect the resistance between terminal component No.1 (12-pin) terminal E (transaxle case side) and body ground.
• Is the resistance within 14-18 ohms?
Yes
Go to Step 8.
No
Go to the next step.
4
INSPECT COUPLER COMPONENT (10-PIN) FOR POOR CONNECTION
• Disconnect the coupler component (10-pin) connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is the terminal normal?
Yes
Go to the next step.
No
Repair or replace the terminal, then go to Step 12.
5
INSPECT RESISTANCE
• Inspect the resistance between coupler component (10-pin) terminal I (part side) and body ground.
• Is the resistance within 14-18 ohms?
Yes
Repair or replace terminal component No.1 (12-pin), then go to Step 12.
No
Go to the next step.
6
INSPECT REDUCTION TIMING SOLENOID VALVE CONNECTOR FOR POOR CONNECTION
• Disconnect the reduction timing solenoid valve connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is the terminal normal?
Yes
Go to the next step.
No
Repair or replace the terminal, then go to Step 12.
7
INSPECT RESISTANCE
• Inspect the resistance between reduction timing solenoid valve connector terminal A (part side) and body ground.
• Is the resistance within 14-18 ohms?
Yes
Repair or replace the coupler component (10-pin), then go to Step 12.
No
Verify the reduction timing solenoid valve installation.
• If the reduction timing solenoid valve is installed correctly, replace the reduction timing solenoid valve, then go to Step 12
8
INSPECT TCM CONNECTOR FOR POOR CONNECTION
• Disconnect the TCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Are the terminals normal?
Yes
Go to the next step.
No
Repair the terminals, then go to Step 12.
9
INSPECT TERMINAL COMPONENT NO.1 (12-PIN) CIRCUIT FOR OPEN CIRCUIT
• Inspect for continuity between TCM terminal 2G (wiring harness-side) and terminal component No.1 (12-pin) terminal E (wiring harness-side).
• Is there continuity between the terminals?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 12.
10
INSPECT TERMINAL COMPONENT NO.1 (12-PIN) CIRCUIT FOR SHORT TO POWER SUPPLY
• Turn the ignition switch to the ON position (engine off).
• Inspect the voltage at terminal component No.1 (12-pin) terminal E (wiring harness-side).
• Is the voltage 0 V?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 12.
11
INSPECT TCM CIRCUIT FOR SHORT TO GROUND
• Turn the ignition switch to the LOCK position.
• Inspect for continuity between TCM terminal 2G (wiring harness-side) and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to the next step.
No
Go to the next step.
12
VERIFY TROUBLESHOOTING OF DTC P0763 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the TCM memory using the WDS or equivalent.
• Drive the vehicle in the D range and make sure that gears shift smoothly from 1GR to 5GR.
• Is the same DTC present?
Yes
Replace the TCM, then go to the next step.
No
Go to the next step.
13
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.