C1945 – OBD-II DTC

OBD-II DTC C1945 – Park Switch Indicates Park with Vehicle Moving

DTC C1945 meaning

DTC C1945 refers to a diagnostic trouble code indicating that the park switch is signaling that the vehicle is in the “Park” position while the vehicle is actually moving. This discrepancy can lead to issues with the vehicle’s transmission and safety systems, as the park switch is crucial for ensuring that the vehicle can only be shifted out of park when it is safe to do so.

DTC C1945 symptoms

Common symptoms associated with DTC C1945 may include:

• Transmission not shifting properly
• Warning lights on the dashboard
• Vehicle may not start or may stall
• Difficulty shifting gears
• Unusual noises from the transmission

DTC C1945 causes

Several factors can lead to the triggering of DTC C1945, including:

• Faulty park switch
• Wiring issues or short circuits in the park switch circuit
• Malfunctioning transmission control module (TCM)
• Mechanical issues within the transmission
• Improperly adjusted or damaged linkage

DTC C1945 seriousness

DTC C1945 is considered a serious issue as it can affect the vehicle’s ability to shift gears safely. If the park switch is malfunctioning, it may lead to unintended vehicle movement, increasing the risk of accidents. It is important to address this code promptly to ensure safe vehicle operation.

How to diagnose DTC C1945

To diagnose DTC C1945, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1945 code.
2. Inspect the park switch for any visible damage or wear.
3. Check the wiring and connectors associated with the park switch for shorts or disconnections.
4. Test the park switch using a multimeter to ensure it is functioning correctly.
5. Examine the transmission control module for any faults or error codes.
6. Perform a road test to see if the issue persists while monitoring the vehicle’s behavior.

How to fix DTC C1945 step-by-step instructions

To fix DTC C1945, follow these steps:

1. Start by addressing any wiring issues found during diagnosis, repairing or replacing damaged wires as necessary.
2. If the park switch is faulty, replace it with a new one.
3. Ensure that the park switch is properly adjusted and aligned.
4. Check the transmission control module for updates or reprogramming if needed.
5. Clear the DTC using an OBD-II scanner after repairs are made.
6. Perform a road test to confirm that the issue has been resolved and that the vehicle operates normally.

How to erase DTC C1945

To erase DTC C1945, 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. 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 reappear.

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