P1748 – OBD-II DTC

OBD-II DTC P1748 – Torque Converter Clutch Solenoid Failied On

DTC P1748 meaning

DTC P1748 refers to a diagnostic trouble code indicating a failure in the Torque Converter Clutch (TCC) solenoid. The TCC solenoid is responsible for controlling the engagement and disengagement of the torque converter clutch, which helps improve fuel efficiency and vehicle performance by locking the torque converter to the engine during certain driving conditions.

DTC P1748 symptoms

Common symptoms associated with DTC P1748 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 P1748 causes

Several factors can lead to the occurrence of DTC P1748, including:

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

DTC P1748 seriousness

DTC P1748 can be considered serious as it affects the vehicle’s transmission performance and fuel efficiency. If left unaddressed, it may lead to further transmission damage or failure, resulting in costly repairs. Additionally, the symptoms may compromise vehicle safety, especially if the engine stalls unexpectedly while driving.

How to diagnose DTC P1748

To diagnose DTC P1748, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1748 code.
2. Check for any additional trouble codes that may provide more context.
3. Inspect the TCC solenoid and its wiring for any visible damage or disconnections.
4. Test the TCC solenoid’s resistance using a multimeter to ensure it is within specifications.
5. Check the transmission fluid level and condition, replacing it if necessary.
6. Examine the transmission control module for faults or issues.

How to fix DTC P1748 step-by-step instructions

To fix DTC P1748, follow these steps:

1. Ensure the vehicle is safely lifted and supported if working underneath.
2. Inspect and repair any damaged wiring or connectors related to the TCC solenoid.
3. Replace the faulty torque converter clutch solenoid if testing indicates it is defective.
4. Change the transmission fluid and filter if they are contaminated or low.
5. Clear the DTC using an OBD-II scanner and take the vehicle for a test drive to verify the repair.
6. Monitor for any reoccurrence of the P1748 code or related symptoms.

How to erase DTC P1748

To erase DTC P1748, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Access the scanner’s menu and select the option to clear or erase trouble codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to ensure the check engine light is off.

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