Faulty TCC solenoid; Wiring or connector fault; Low or degraded fluid; Worn torque converter clutch; Valve body problem.

P0740: Torque Converter Clutch Solenoid Circuit/Open

Q: What does P0740 mean?

P0740: Torque Converter Clutch Solenoid Circuit/Open. The torque converter clutch (TCC) locks the converter at cruising speed to eliminate slip. This code points to an electrical fault in the TCC solenoid circuit.

Q: Is it safe to drive with P0740?

Severity: Moderate. Drivable with care. Diagnose soon: performance, economy or other components can be affected.

P0740 means Torque Converter Clutch Solenoid Circuit/Open. The torque converter clutch (TCC) locks the converter at cruising speed to eliminate slip. This code points to an electrical fault in the TCC solenoid circuit.

CodeP0740

SystemTransmission

SeverityModerate

TypeGeneric powertrain

Can I keep driving? Drivable with care. Diagnose soon: performance, economy or other components can be affected.

Common symptoms

Check engine light on
Higher RPM at highway speed and worse fuel economy (stuck off)
Stalling when coming to a stop (stuck on)
Shudder at light throttle

Possible causes

Faulty TCC solenoid
Wiring or connector fault
Low or degraded fluid
Worn torque converter clutch
Valve body problem

How to diagnose P0740

Check fluid level and condition.
Check the solenoid circuit and resistance.
Command TCC apply on a scan tool and watch slip RPM.

What the code means, digit by digit

PPowertrain0Generic (SAE) code7Sub-system40Specific fault

Generic codes have the same definition on every OBD-II vehicle (petrol cars from model year 1996 in the US, 2001 in the EU; diesels later). Manufacturers can add their own enhanced codes; those are not listed here.

Related codes

General guidance only. Fault codes describe what the engine computer saw, not which part failed: confirm with testing before replacing parts, and follow the vehicle's service information.