P0740

TECHNICAL DESCRIPTION
- When a malfunction of the torque converter clutch or its related system is detected, the transaxle control CPU inside the powertrain control module (PCM) outputs a malfunction signal to the engine control CPU in the PCM.

DTC SET CONDITIONS

Check Area, Judgement Criteria
- Failed signal of the torque converter clutch or its related system is input to the engine control CPU from the transaxle control CPU.

TROUBLESHOOTING HINTS
The most likely causes for this code to be set are:
- Torque converter clutch or its related system failed.
- Open or shorted torque converter clutch or its related system circuit, or loose connector.
- PCM failed.

DIAGNOSIS
Required Special Tool:
MB991502: Scan Tool (MUT-II)

CAUTION: To prevent damage to the scan tool, make sure the ignition switch is off before connecting or disconnecting the scan tool.




STEP 1. Using scan tool MB991502, read the A/T diagnostic trouble code (DTC).
If the A/T-DTC is displayed, refer to Diagnosis.
If the A/T-DTC is not displayed, it is suspected that an MFI-DTC has not been erased after repairing the A/T component.
If DTC P0740 is displayed again after the MFI-DTC has been erased, replace the PCM. Then check that the DTC is not output.