P0744 Code: Torque Converter Clutch Circuit Intermittent — Meaning & Fix

Sun West Transmissions — Glendale, AZ. Free estimates, honest diagnosis and a 3-year / 40,000-mile warranty on qualifying rebuilds and replacements.

The P0744 code is a torque converter clutch code, and the key word in its description is “intermittent.” The transmission computer saw the converter clutch circuit work, stop working, then work again. Because the problem comes and goes, it is easy to ignore while the vehicle still seems to drive fine.

Here is what P0744 means, what causes it and how Sun West Transmissions in Glendale tracks it down.

What P0744 Means

The standard definition of P0744 is “Torque Converter Clutch Circuit Intermittent.” Exact wording varies by manufacturer, and some call it a TCC solenoid circuit code. Some manufacturers also use P0744 for a lockup clutch that is not working as commanded, so the definition for your specific vehicle matters.

The torque converter clutch (TCC), often called the lockup clutch, connects the engine directly to the transmission once you reach a steady cruising speed. Lockup removes converter slip, which lowers engine RPM, improves fuel economy and cuts heat. The computer applies the clutch through a solenoid, and P0744 says that control signal is not staying steady. To understand the computer side, see what is a transmission control module.

Common Causes of P0744

• A loose, corroded or damaged TCC connector or wiring harness
• A failing TCC solenoid that works when cool but cuts out when hot
• A worn internal harness or a leaking pass-through connector where the wiring enters the transmission case
• Low, burnt or contaminated transmission fluid
• A transmission control module (TCM) fault, which is less common

Intermittent faults are often heat related. Transmission wiring runs close to the exhaust, and Phoenix summers add even more heat, so a weak connection may only drop out once everything is fully warmed up.

Symptoms of P0744

• Check engine light
• Shudder or a surging feel at steady speeds as lockup applies and releases. See torque converter shudder
• Engine RPM that rises and falls on the highway without any change in throttle
• Higher cruising RPM and lower fuel economy when lockup stays off
• A transmission that runs hotter than normal
• Sometimes no noticeable symptoms, especially early on

Can I Keep Driving?

Most vehicles with P0744 still drive, and many feel normal around town. The concern is heat. When lockup cuts in and out, the converter slips more, and slipping creates heat that breaks down fluid and wears friction material. In Arizona summer traffic, that damage adds up quickly.

Drive gently, avoid heavy loads, and schedule a diagnosis soon. If you notice slipping, a burnt smell, harsh shifts or limp mode, stop driving and call us. Our guide on whether it is safe to drive with a bad transmission explains more.

How Sun West Diagnoses P0744

Intermittent codes take patience and good data. At our Glendale shop, we:

• Read all modules with a professional scan tool and review freeze-frame data showing speed, temperature and gear when the fault set
• Inspect the TCC wiring and connectors, then check voltage and resistance while flexing the harness to catch a dropout
• Test the TCC solenoid and command it on and off with the scan tool
• Check fluid level, condition and smell for signs of overheating or wear
• Pressure test the transmission when the data points to a hydraulic problem
• Road test with live data, comparing commanded lockup to actual converter slip

Learn more on our computer transmission diagnostics page.

Repair Options

The right repair depends on what the testing shows:

• Wiring or connector repair: cleaning, repinning or replacing damaged terminals and harness sections, including internal harnesses and pass-through connectors
• Solenoid or valve body work: replacing a failing TCC solenoid, or repairing the valve body if a sticking valve is involved. See solenoid replacement and valve body repair
• TCM programming: software updates or module replacement when the computer itself is at fault. See TCM programming
• Converter replacement or rebuild: only if testing shows internal damage, such as a worn converter clutch or burnt clutches. See torque converter replacement and transmission rebuild

Many P0744 repairs are electrical and do not require a rebuild. Call (623) 473-9800 for a free quote.

Related Codes

These related codes sometimes appear with P0744:

• P0740 – Torque converter clutch circuit
• P0741 – Torque converter clutch performance or stuck off
• P0742 – Torque converter clutch stuck on
• P0700 – Transmission control system malfunction, a general flag that the TCM has stored a code

P0744 Code FAQ

Will clearing the code fix P0744?

No. Clearing it turns the light off for a while, but an intermittent fault will come back. It also erases freeze-frame data that helps pinpoint when the dropout happens.

Is P0744 the same as P0741?

No. P0741 points to a converter clutch that is not applying or holding as commanded, while P0744 points to an on-and-off problem in the control circuit. The two can appear together.

How much does it cost to fix P0744?

It depends on the cause and the vehicle, since a connector repair is a very different job than a converter replacement. Call (623) 473-9800 for a free quote.