CarSense › Trouble codes › P0740

P0740: Torque Converter Clutch Circuit Malfunction

What this check-engine code means in plain English, what usually causes it, and what a fix typically costs.

Severity: Monitor — not an emergency, but address soon

What P0740 means

The torque converter clutch (TCC) is not engaging or disengaging properly, or the control circuit has failed. The powertrain control module (PCM) detected that the torque converter lockup mechanism is not responding as commanded, which can reduce fuel economy and cause transmission overheating.

What causes P0740?

Likely
Faulty torque converter clutch solenoidThe solenoid that controls lockup engagement has failed electrically or mechanically.
Likely
Dirty or low transmission fluidContaminated or insufficient fluid prevents proper hydraulic pressure for clutch operation.
Possible
Wiring or connector issuesDamaged wiring, corroded connectors, or poor grounds in the TCC solenoid circuit.
Less common
Failed torque converterInternal mechanical failure of the torque converter clutch assembly itself.

Is P0740 safe to drive?

Drive it?
Usually yes, short-term
Watch for
Transmission overheating, poor fuel economy, shuddering
DIY-friendly?
Fluid check is DIY; solenoid replacement requires moderate skill; converter replacement is professional work

You can typically drive short distances, but prolonged driving may cause transmission overheating and reduced fuel economy. The transmission may shift roughly or feel like it's slipping at highway speeds. Address within a few days to prevent potential transmission damage.

P0740 repair cost

~$150 – $1400+

Industry-average estimates. Cost depends on whether it's a simple solenoid replacement, fluid service, or requires torque converter replacement with transmission removal.

Which one is it for your car?

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