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P0740

BG: DTC P0740 - TORQUE CONVERTER CLUTCH SYSTEM MALFUNCTION

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

TROUBLE SYMPTOM:
- No lock-up (after engine warm-up)
- No shift or excessive tight corner "braking"

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How to Clear Diagnostic Trouble Codes. Clearing Diagnostic Trouble Codes





WIRING DIAGRAM

10BG1: CHECK ANY OTHER DTC ON DISPLAY.

CHECK: Is there any other DTC on display?

YES: Inspect the relevant DTC using "10. Diagnostics Chart with Trouble Code".

NO: Go to step 10BG2.

10BG2: CHECK DUTY SOLENOID B CIRCUIT.
Check duty solenoid B circuit.

CHECK: Is there any trouble in duty solenoid B circuit?

YES: Repair or replace duty solenoid B circuit.

NO: Go to step 10BG3.

10BG3: CHECK THROTTLE POSITION SENSOR CIRCUIT.
Check throttle position sensor circuit.

CHECK: Is there any trouble in throttle position sensor circuit?

YES: Repair or replace throttle position sensor circuit.

NO: Go to step 10BG4.

10BG4: CHECK TORQUE CONVERTER TURBINE SPEED SENSOR CIRCUIT.
Check torque converter turbine speed sensor circuit.

CHECK: Is there any trouble in torque converter turbine speed sensor circuit?

YES: Repair or replace torque converter turbine speed sensor circuit.

NO: Go to step 10BG5.

10BG5: CHECK ENGINE SPEED INPUT CIRCUIT.
Check engine speed input circuit.

CHECK: Is there any trouble in engine speed input circuit?

YES: Repair or replace engine speed input circuit.

NO: Go to step 10BG6.

10BG6: CHECK INHIBITOR SWITCH CIRCUIT.
Check inhibitor switch circuit.

CHECK: Is there any trouble in inhibitor switch circuit?

YES: Repair or replace inhibitor switch circuit.

NO: Go to step 10BG7.

10BG7: CHECK BRAKE LIGHT SWITCH CIRCUIT.
Check brake light switch circuit.

CHECK: Is there any trouble in brake light switch circuit?

YES: Repair or replace brake light switch circuit.

NO: Go to step 10BG8.

10BG8: CHECK ATF TEMPERATURE SENSOR CIRCUIT.
Check ATF temperature sensor circuit.

CHECK: Is there any trouble in ATF temperature sensor circuit?

YES: Repair or replace ATF temperature sensor circuit.

NO: Go to step 10BG9.

10BG9: CHECK POOR CONTACT.
Check poor contact in TCM connector.

CHECK: Is there poor contact in TCM connector?

YES: Repair poor contact in TCM connector.

NO: Go to step 10BG10.

10BG10: CHECK MECHANICAL TROUBLE.
Check mechanical trouble in automatic transmission.

CHECK: Is there any mechanical trouble in automatic transmission?

YES: Repair or replace automatic transmission.

NO: Replace TCM.