What is the P0743 fault number? What is Torque Converter Clutch Solenoid Electrical Circuit Malfunction? How do you fix the P0743 fault code What are the causes and symptoms of the P0743 error code?
What is the P0743 fault code? What does it all mean?
The torque converter clutch links the transmission and engine. It plays an important part in improving transmission efficiency at highway speeds, increasing fuel consumption, managing transmission fluid temperature and reducing vehicle emission. If your vehicle’s primary computer (Powertrain Controller Module or PCM), detects a problem in the torque converter, it might log error code P0743 to your vehicle’s onboard diagnostic system. This information may help you to better understand the trouble code.
P0743 Diagnostic trouble code DTC means “Torque Converter Clutch Clutch Solnoid Electrical Circuit Malfunction”. The PCM adjusts when it detects a problem with the torque conversion clutch (TCC), solenoid, or circuit.
The torque converter has a clutch which creates a “mechanical locking” between the engine & transmission. The working logic of the torque converter is identical to that of a manual transmission. The electronic solenoid is used to engage the converter clutch by the transmission control module (TCM).
To achieve a 1:1 ratio between the transmission input shaft speed and the torque converter rotation rate, the clutch locking function must be used. This setting prevents power loss that you might experience with a fluid/hydraulic lock. This condition allows the engine to run at a low speed and under load.
If it detects an electrical fault in the torque converter solenoid electrical circuit, the powertrain control module will set fault code “P0743”.
What causes the P0743 Fault code?
- – The solenoid for the defective torque converter clutch solenoid
- – Defective torque converter
- – Defective valve body
- – Oily transmission oil can restrict hydraulic passage
- – Transmission oil at a low level
- – Internal transmission failures
- – The defective transmission control or PCM
What are the symptoms of the P0743 Fault Code?
- – Illumination for the check engine light
- Highway speeds: Higher RPMs
- – Increased fuel consumption
- – Vehicle can enter safe mode (“Limp Mode”)
- Vehicle shaking
- – Gearbox overheating
- Transmission slippage, misfire, or other problems with the engine performance of the vehicle may sometimes occur while it is stopped.
How to Fix the P0743 Fault Code
- – To see if it returns, the code must be reset.
- If the code is returned, it is important to check the transmission harness as well as the connections. You must correct any defective wiring and loose connections.
- – Make sure to check the oil level and condition of your gearbox. It is necessary to replace the transmission oil if it is not present.
- – Check to see if there is any blockage in the transmission oil passages. It should be repaired if there is one.
- – Check the fuses. Verify that the transmission case is properly grounded to the battery and the body.
- – Locate the wires that correspond to the torque converter clutch. There are usually two wires in the solenoid, one for power and another for ground. You can apply power or ground to the solenoid and it will click.
- If the solenoid doesn’t click, check the wiring from and to the sensor. The low ohm reading of the solenoid should fall between.02 to.05. This can vary from manufacturer to manufacturer. This should be checked with the service manual.
- If the problem persists, replace the solenoid of the torque converter. It is worse to replace the torque converter.
- – If none of these options work, you should replace the transmission control module (TCM), or PCM.
How serious is the P0743 fault code?
It can be dangerous to drive a vehicle with the P0743 fault code. You may experience a stalling problem if you stop at traffic lights or stop signs. This can lead to dangerous situations. It’s a smart idea to take your vehicle to a mechanic, even if you don’t see any other signs of malfunction than the code P0743.
