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P0743ModerateTransmission

P0743: Torque Converter Clutch Circuit Electrical

3 vehicles · 2 makes · $150-$3,000 repair

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Most Reported On

1998-2011Ford Crown Victoria2007-2020GMC Sierra 3500HD1990-1997Ford Aerostar

P0743 is an OBD-II diagnostic trouble code meaning “Torque Converter Clutch Circuit Electrical.” This code indicates an electrical fault in the torque converter clutch (TCC) circuit, the wiring and solenoid that lock the torque converter so the engine and transmission turn together for better efficiency at cruising speed. The transmission computer commands the TCC solenoid on and off, and when it sees an open, short, or out-of-range electrical signal in that circuit, it sets this code. You may notice slipping, harsh or no lockup, reduced fuel economy, or the transmission staying in a lower gear. Because it is an electrical-circuit code, the problem is usually in the solenoid, connector, or wiring rather than worn mechanical clutch material. This code is most commonly reported on 1998-2011 Ford Crown Victoria, 2007-2020 GMC Sierra 3500HD, and 1990-1997 Ford Aerostar, with repair costs ranging from $150 to $3,000.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (3)
  • Related Codes
  • FAQ
  • Sources (4)

Makes

  • Ford2
  • GMC1
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Common Causes

1Failed torque converter clutch (TCC) solenoid
2Open, shorted, or corroded wiring in the TCC circuit
3Damaged or loose transmission connector
4Low or contaminated/dirty transmission fluid
5Faulty transmission valve body or internal harness
6Failed torque converter (internal clutch)
7Faulty transmission control module (TCM/PCM)

Typical Repair Cost

$150 - $3,000

Based on 3 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0743, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
Check Price on Amazon
Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (3)

Ford P0743 page →
Crown VictoriaCritical

4R70W/4R75W Transmission Shift Solenoid Pack Failure

1998-2011$300-$1,2002,400 reports
AerostarCritical

A4LD Automatic Transmission Premature Failure

1990-1997$1,200-$3,000220 reports
GMC P0743 page →
Sierra 3500HDModerate

Allison 1000/2000 Series Transmission Torque Converter Shudder

2007-2020$150-$2,200310 reports

Related Codes (8)

P0740Torque Converter Clutch Circuit MalfunctionP0741Torque Converter Clutch Circuit Performance/Stuck OffP0742Torque Converter Clutch Circuit Stuck OnP0744Torque Converter Clutch Circuit IntermittentC0700Transmission Control Module CommunicationP0218Transmission Over Temperature ConditionP0500Vehicle Speed Sensor MalfunctionP0700Transmission Control System Malfunction

FAQ

What does P0743 mean?

P0743 stands for "Torque Converter Clutch Circuit Electrical." This code indicates an electrical fault in the torque converter clutch (TCC) circuit, the wiring and solenoid that lock the torque converter so the engine and transmission turn together for better efficiency at cruising speed. The transmission computer commands the TCC solenoid on and off, and when it sees an open, short, or out-of-range electrical signal in that circuit, it sets this code. You may notice slipping, harsh or no lockup, reduced fuel economy, or the transmission staying in a lower gear. Because it is an electrical-circuit code, the problem is usually in the solenoid, connector, or wiring rather than worn mechanical clutch material.

What are the most common causes of P0743?

The most common causes of P0743 are: Failed torque converter clutch (TCC) solenoid, Open, shorted, or corroded wiring in the TCC circuit, Damaged or loose transmission connector, Low or contaminated/dirty transmission fluid, Faulty transmission valve body or internal harness, Failed torque converter (internal clutch), Faulty transmission control module (TCM/PCM). The specific cause varies by vehicle.

How much does it cost to fix P0743?

Repair costs for P0743 range from $150 to $3,000, depending on the vehicle and root cause.

Which vehicles are affected by P0743?

Au7o has documented P0743 across 3 vehicle models from 2 manufacturers: Ford, GMC.

Sources (4)

  • videoYouTube - How to Replace 4R70W Transmission Shift Solenoid Pack - EricTheCarGuy
  • mediaFord Ranger A4LD Automatic Transmission - The Ranger Station
  • mediaFord A4LD Transmissions Specs - TransmissionRepairCostGuide
  • ForumA4LD Shifting issues 2nd missing - Ford Explorer Forums

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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