P0743 OBD-II Trouble Code: Torque Converter Clutch Circuit Electrical

Code definition

The P0743 trouble code means that the powertrain control module has found in abnormality with the torque converter clutch circuit.

What the P0743 code means

When the powertrain control module has detected that there is a variation from the manufacturer’s specifications with the torque converter clutch application, this code will be stored. Keep in mind that some applications will require multiple failure cycles before the Check Engine light comes on.

What causes the P0743 code?

The following are some of the most common causes for the P0743 code:

• Faulty torque converter clutch solenoid
• Defective torque converter
• Mechanical internal transmission failure
• Hydraulic blockages inside internal transmission fluid passages
• Low transmission fluid
• Dirty transmission fluid
• A faulty transmission control module or faulty PCM

What are the symptoms of the P0743 code?

These symptoms detected with AP 0743 code can vary substantially. In some cases, the driver might not notice any problems at all what they are behind the wheel. In other cases, they will notice that the engine has issues and it may stall when they have come to stop and the engine is still idling. This can happen at a stop sign or stop light, for example. Some of the other symptoms include trouble shifting, a slipping transmission, lower fuel efficiency, and an overheating transmission. In addition, the Check Engine light will often come on when this code is stored.

How does a mechanic diagnose the P0743 code?

When the mechanic is diagnosing P0743 code, he or she will begin by connecting their OBD-II scanner to the vehicle’s onboard computer. The onboard computer will have stored the trouble code and data from the vehicle. The scanner checks that data. The mechanic then wants to reset the trouble code and drive the vehicle. They do this so they can see if the code comes back. If it does, that means it was not set by mistake. Then, they can continue with the diagnosis to determine what is causing the P0743 code.

Common mistakes when diagnosing the P0743 code

a number of technicians have found that mechanics have replaced the lock up solenoids and torque converters when they do not need to be replaced. In those cases, the mechanics have overlooked the simpler problem of wire malfunctions affecting the torque converter.

How serious is the P0743 code?

If the vehicle is suffering from the symptoms of the P0743 code, then it can be very problematic to drive. The driver might have issues when it comes to shifting the vehicle, and they may notice that their transmission is overheating, which could cause other problems. It can also be a problem to have a vehicle stall when it comes to rest at a stop sign or stoplight. In some cases, it could even be dangerous. Even in those cases when the driver doesn’t notice any issues, if the P0743 code has been stored, it’s a good idea to take the vehicle to a mechanic.

What repairs can fix the P0743 code?

The following are some of the repairs that a technician might make to fix the P0743 code:

• First, they check to make sure the trouble code is legitimate by resetting, it driving the vehicle, and seeing if it comes back
• Mechanic will then check the wiring and connections to make sure everything is connected properly and there are no issues
• The mechanic will also check to make sure there is plenty of transmission fluid, and that it is not dirty or contaminated
• The mechanic will check for blockages in the transmission fluid passages
• The mechanic may need to replace the torque converter clutch solenoid or the torque converter
• In rare cases, they may need to replace a transmission control module or PCM

Additional comments for consideration regarding the P0743 code

Regardless of whether the driver notices any issues well driving the vehicle, if the P0743 code has been stored, the best course of action is to take it into a mechanic.

Need help with a P0743 code?

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