P1746 – OBD-II DTC

OBD-II DTC P1746 – Torque Converter Clutch Control Error

DTC P1746 meaning

DTC P1746 refers to a Torque Converter Clutch Control Error. This diagnostic trouble code indicates that the engine control module (ECM) has detected a malfunction in the torque converter clutch (TCC) system. The TCC is responsible for locking the torque converter to improve fuel efficiency and reduce engine load during cruising conditions. When this system fails, it can lead to various performance issues.

DTC P1746 symptoms

Common symptoms associated with DTC P1746 may include:

• Engine stalling or hesitation during acceleration
• Increased engine RPMs while driving
• Poor fuel economy
• Transmission slipping or harsh shifting
• Illuminated check engine light

DTC P1746 causes

Several factors can contribute to the occurrence of DTC P1746, including:

• Faulty torque converter clutch solenoid
• Wiring issues or poor connections in the TCC circuit
• Low transmission fluid levels or dirty fluid
• Faulty transmission control module (TCM)
• Mechanical issues within the transmission

DTC P1746 seriousness

The seriousness of DTC P1746 can vary. While it may not cause immediate safety concerns, it can lead to:

• Reduced fuel efficiency
• Increased wear on transmission components
• Potential for more severe transmission damage if left unaddressed

It is advisable to diagnose and repair the issue promptly to avoid further complications.

How to diagnose DTC P1746

To diagnose DTC P1746, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1746 code.
2. Check for any additional trouble codes that may provide more context.
3. Inspect the transmission fluid level and condition.
4. Examine the wiring and connectors related to the torque converter clutch solenoid.
5. Test the torque converter clutch solenoid for proper operation.
6. Check the transmission control module for faults.

How to fix DTC P1746 step-by-step instructions

To fix DTC P1746, follow these step-by-step instructions:

1. Ensure the vehicle is safely lifted and supported if necessary.
2. Check and top off the transmission fluid if low.
3. Inspect the wiring and connectors for damage or corrosion, and repair as needed.
4. Replace the torque converter clutch solenoid if it is faulty.
5. Clear the DTC using an OBD-II scanner.
6. Test drive the vehicle to see if the code returns.

How to erase DTC P1746

To erase DTC P1746, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the vehicle to ensure the code does not return.

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