P0790 – OBD-II DTC

OBD-II DTC P0790 – Shift/Timing Solenoid Range/Performance

DTC P0790 meaning

DTC P0790 refers to a problem with the shift or timing solenoid in an automatic transmission. This code indicates that the solenoid’s range or performance is outside the expected parameters. The shift solenoid is responsible for controlling the flow of transmission fluid, which in turn affects gear shifting. When the Engine Control Module (ECM) detects an issue with the solenoid’s operation, it triggers this diagnostic trouble code.

DTC P0790 symptoms

Common symptoms associated with DTC P0790 may include:

• Delayed or harsh shifting between gears
• Slipping transmission
• Check Engine Light illuminated
• Unusual noises from the transmission
• Inability to shift into certain gears

DTC P0790 causes

Several factors can lead to the triggering of DTC P0790, including:

• Faulty shift solenoid
• Wiring issues or poor connections
• Low transmission fluid levels
• Contaminated transmission fluid
• Faulty transmission control module (TCM)

DTC P0790 seriousness

DTC P0790 is considered a serious issue as it can affect the vehicle’s drivability and safety. If left unaddressed, it may lead to further transmission damage, increased repair costs, and potential safety hazards while driving. It is advisable to diagnose and repair the issue promptly to avoid complications.

How to diagnose DTC P0790

To diagnose DTC P0790, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P0790 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 shift solenoid for damage or corrosion.
5. Test the shift solenoid’s resistance and operation using a multimeter.
6. Check the transmission control module for faults.

How to fix DTC P0790 step-by-step instructions

To fix DTC P0790, follow these steps:

1. Address any low or contaminated transmission fluid by replacing it and ensuring the correct level.
2. Repair or replace any damaged wiring or connectors related to the shift solenoid.
3. If the shift solenoid is faulty, replace it with a new one.
4. Clear any stored trouble codes using an OBD-II scanner.
5. Test drive the vehicle to ensure the issue is resolved and the Check Engine Light does not reappear.

How to erase DTC P0790

To erase DTC P0790, 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 Codes” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the vehicle to check if the code reappears.

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