P0740 HONDA - Transmission Lock-Up Control System Fault
- Low transmission fluid level
- Dirty transmission fluid
- Faulty torque converter clutch solenoid valve
- Torque converter clutch solenoid valve harness is open or shorted
- Torque converter clutch solenoid valve circuit poor electrical connection
Tech notesOn some Honda vehicles, the P0740 code may be set by an overheating torque converter problem which is caused by an insufficient flow to the torque converter release circuit.
User Submitted Video
When is the code detected?Diagnostic trouble code P0740 is detected when TCM detects an improper voltage drop when it tries to operate the solenoid valve.
- Engine Light ON (or Service Engine Soon Warning Light)
- Transmission shift shock
- Vehicle may not shift into the highest gear
P0740 Honda DescriptionThe torque converter clutch solenoid valve is activated, with the gear in D4, by the Transmission Control Module (TCM) in response to signals sent from the vehicle speed and the Engine Control Module (ECM). Lock-up piston operation will then be controlled. When the torque converter clutch solenoid valve is activated, the torque converter lockup clutch will engage creating a 1 to 1 RPM ratio between the transmission input shaft and the rotational speed of the torque converter.
Lock-up operation, however, is prohibited when A/T fluid temperature is too low.
When the accelerator pedal is depressed (less than 2/8) in lock-up condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.
Need more help?Get the P0740 Honda code diagnosed by a professional: Find a repair shop in your area
P0740 HONDA CommentsHelp us improve AutoCodes.com. Leave a comment below or tell us if the information above help you fix the code. What are the symptoms on your vehicle for the P0740 Honda code? Have you replaced any parts?
Any information is appreciated. Thanks