P1744: Torque converter clutch slipping or not working as expected (Ford, Lincoln, Mercury, Mazda)

Torque converter clutch performance

Severity: Inspect soon

The lock-up clutch is a monitored transmission output, and a code reference rates P1744 as severe because slipping can damage the transmission.

It gets more serious if:

Not verified: The O/D OFF light blinks, the transmission slips, or it goes into limp-home mode. A Mazda owner reported slipping while passing, but we found no source saying whether you must stop

Source: how we rate severity

P1744 in short

On Ford, Lincoln, Mercury and Mazda, P1744 means the torque converter clutch is slipping or not locking up as commanded. Ford bulletins trace it to torque converter damage, a torn converter seal or a sticking lock-up valve. It often comes with P0741. Have it inspected soon to avoid further damage.

At steady speed the torque converter clutch locks the engine to the transmission to stop converter slip and save fuel. The computer compares engine and turbine speed; on Ford, Lincoln, Mercury and Mazda, P1744 sets when the clutch slips more than expected or does not apply.

Ford bulletins give different causes by model: internal torque converter damage on the 2013–2015 Escape 1.6L, a torn inner converter seal on several 2013 models, and a sticking lock-up valve in the main control on early 10R80 trucks.

Some cars show only the light; others shudder, rev higher at cruise or slip. Mazda owners of the 1996–1997 626 reported a blinking O/D OFF light and transmission failure with P1744.

Pick your make

P1744 is a manufacturer-specific code: its meaning depends on who built the car.

Other makes: meaning not verified. Check with a scan tool that reads manufacturer definitions.

Most likely causes

Cause 1: Internal torque converter damage or torn converter seal
Supported by vehicle data
Why it ranks here
Ford bulletins name converter damage on the 2013–2015 Escape 1.6L and a torn inner converter seal on several 2013 models for P0741 and P1744.
What would change this
Rises on a covered vehicle or if P0741 is stored with no other symptom.
Cause 2: Sticking lock-up control valve in the main control (Ford 10R80)
Supported by vehicle data
Why it ranks here
Ford traced P0741 and P1744 on early 2017–2018 10R80 vehicles to a sticking torque converter clutch valve and replaces the main control.
What would change this
Rises on an F-150, Expedition, Mustang or Navigator built on or before 20 November 2017.
Cause 3: Fluid, lock-up solenoid or wiring fault
Common general cause
Why it ranks here
A code reference lists fluid condition, the solenoid and wiring among common causes, and the solenoid is a monitored output.
What would change this
Rises if fluid is low or burnt, or a solenoid circuit code is also stored.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

Step 1: Read codes from the engine and transmission modules with a scan tool that supports both, before anything is cleared.
Low riskTool: scan tool that reads the transmission module
- IfOther transmission codes are stored with P1744
  It meansA lock-up solenoid circuit code with P1744 points to wiring or the solenoid first.
  Points to: Fluid, lock-up solenoid or wiring fault
- IfP1744 alone
  It meansCheck for a bulletin.
  Go to step 2
Step 2: Check for a P1744 bulletin for your VIN at a dealer or on the NHTSA site.
Low risk
- IfA 2013–2015 Escape 1.6L EcoBoost with only P0741 and/or P1744
  It meansFord repairs or replaces the torque converter.
  Points to: Internal torque converter damage or torn converter seal
- IfA 2013 Edge, Flex, Taurus, Explorer, MKS or MKT with no other symptom
  It meansFord points to a torn inner converter seal.
  Points to: Internal torque converter damage or torn converter seal
- IfA 2017–2018 10R80 F-150, Expedition, Mustang or Navigator built on or before 20 November 2017
  It meansFord replaces the main control.
  Points to: Sticking lock-up control valve in the main control (Ford 10R80)
- IfNo bulletin applies
  It meansA shop needs to check fluid and lock-up operation.
  Go to step 3
Step 3: Have a shop check fluid level and condition, then watch commanded and actual converter slip on a scan tool during a road test.
Best left to a shopTool: scan tool with live transmission data
Warning:Shop test. It needs the maker's procedure and a road test.
- IfFluid is low, burnt or full of debris
  It meansInternal wear is likely.
  Points to: Internal torque converter damage or torn converter seal
- IfSlip stays high when lock-up is commanded with good fluid
  It meansThe converter or its control valve is the likely fault.
  Points to: Sticking lock-up control valve in the main control (Ford 10R80)

Symptoms

Check engine light, sometimes with no other symptom
Shudder or higher engine speed at steady cruise
Worse fuel economy
O/D OFF light blinking on some Mazdas Gets more serious: stop and have it checked.
Transmission slipping or stuck in one gear Gets more serious: stop and have it checked.

How to fix

Step 1: Do not clear the code before the transmission module has been read.
Step 2: Ask a dealer whether your VIN has an open P1744 bulletin. Ford has issued several.

Parts and cost context

Transmission control module (TCM):P1744 is a lock-up performance fault; Ford bulletins fix it in the torque converter or main control, not by replacing the transmission computer.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Ford

2013–2015 · Escape · 1.6L
Supported by vehicle data
Ford TSB 19-2100 traces P0741 and/or P1744 on the 1.6L EcoBoost to internal torque converter damage. The bulletin is on NHTSA, but whether it is still current is not verified, so it is labelled vehicle data rather than confirmed.
2017–2018 · F-150
Supported by vehicle data
Ford TSB 20-2117 traces P0741 and P1744 on early 10R80 vehicles to a sticking lock-up valve in the main control. The bulletin is on NHTSA, but whether it is still current is not verified, so it is labelled vehicle data rather than confirmed.
2013 · Edge
Supported by vehicle data
Ford ASI-32271 links P0741 and P1744 with no other symptoms to a torn inner torque converter seal on several 2013 models. The bulletin is on NHTSA, but whether it is still current is not verified, so it is labelled vehicle data rather than confirmed.

14964Status unverified
MIL with P1744 (TCC slippage detected)
2000–2001zx2 · issued June 1, 2001 · NHTSA 622755
Gives P1744 as transmission / torque converter clutch slippage detected. Only the NHTSA flat-file summary was read, not the bulletin itself.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
TSB 19-2100Status unverified
MIL with only P0741 and/or P1744
2013–2015escape · 1.6L · issued April 11, 2019 · NHTSA 10159457
Internal torque converter damage; repair or replace the converter. Only the NHTSA flat-file summary was read, not the bulletin itself.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
ASI-32271Status unverified
P0741 and P1744 with no other symptoms
2013edge, flex, taurus, explorer · issued June 1, 2013 · NHTSA 10053427
May be caused by a torn inner torque converter seal. Also lists the Lincoln MKS and MKT. Only the NHTSA flat-file summary was read, not the bulletin itself.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
TSB 20-2117Status unverified
10R80: MIL with P0741 and P1744
2017–2018f-150, expedition, mustang · issued April 15, 2020 · NHTSA 10174402
On vehicles built on or before 20 November 2017, a sticking torque converter clutch valve in the main control. Also lists the Lincoln Navigator. Only the NHTSA flat-file summary was read, not the bulletin itself.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Mazda

1996–1997 · 626
Supported by vehicle data
Owners report Mazda dealers reading P1744 with P0741 on transmissions that later slipped or failed; the O/D OFF light blinked in one case.

All Transmission codes

P1744 questions

What is the difference between P1744 and P0741?

Both are lock-up clutch performance faults and usually appear together on Ford and Mazda. Ford bulletins treat them as one problem with the same repair.

Sources and review

Cal. Code Regs. Tit. 13, § 1968.2 — Malfunction and Diagnostic System Requirements (OBD II) — California Air Resources Board (via Cornell LII)
P1744 OBD-II Trouble Code: Torque Converter Clutch System Performance — Kelley Blue Book
NHTSA complaint ODI 751990: 1997 Mazda 626 dealer code readout — NHTSA Office of Defects Investigation
Ford TSB 19-2100: MIL with only P0741 and/or P1744 — Ford Motor Company / NHTSA , April 11, 2019
Ford ASI-32271: P0741 and P1744 with no other symptoms — Ford Motor Company / NHTSA , June 1, 2013
Ford TSB 20-2117: 10R80: MIL with P0741 and P1744 — Ford Motor Company / NHTSA , April 15, 2020
DTC P0700 — Saab 9-5 (9650) 2010 Workshop Information System — SaabWISOnline (community rehost of Saab/GM service information)
NHTSA complaint ODI 738516: 1996 Mazda 626 dealer code readout — NHTSA Office of Defects Investigation
Ford 14964: MIL with P1744 (transmission / TCC slippage detected) — Ford Motor Company / NHTSA , June 1, 2001
Ford 5374: 4R100: P1744 (torque converter clutch slippage detected) — Ford Motor Company / NHTSA , December 1, 1998
Ford 03123: Torque converter clutch not engaging, P0741 or P1744 — Ford Motor Company / NHTSA , June 23, 2003

Last reviewed: October 15, 2026
Written by: Saurabh K.
Editorial review: Pending
Technician review: Technician review pending

This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error

Severity: Inspect soon

Pick your make

Most likely causes

Cause 1: Internal torque converter damage or torn converter seal

Cause 2: Sticking lock-up control valve in the main control (Ford 10R80)

Cause 3: Fluid, lock-up solenoid or wiring fault

What to test first

Step 1: Read codes from the engine and transmission modules with a scan tool that supports both, before anything is cleared.

Step 2: Check for a P1744 bulletin for your VIN at a dealer or on the NHTSA site.

Step 3: Have a shop check fluid level and condition, then watch commanded and actual converter slip on a scan tool during a road test.