C1170 – OBD-II DTC

OBD-II DTC C1170 – PRNDL Switch Circuit Failure

DTC C1170 meaning

DTC C1170 refers to a fault in the PRNDL (Park, Reverse, Neutral, Drive, Low) switch circuit. This switch is crucial for the proper functioning of the transmission system, as it communicates the gear selection to the vehicle’s engine control module (ECM). When the ECM detects an issue with the PRNDL switch circuit, it triggers the C1170 diagnostic trouble code, indicating a malfunction that needs to be addressed.

DTC C1170 symptoms

Common symptoms associated with DTC C1170 may include:

• Transmission not shifting properly
• Inability to start the vehicle
• Check Engine Light illuminated
• Erratic or incorrect gear display on the dashboard
• Vehicle may go into limp mode

DTC C1170 causes

Several factors can lead to the occurrence of DTC C1170, including:

• Faulty PRNDL switch
• Wiring issues, such as shorts or open circuits
• Corroded or loose connectors
• Faulty transmission control module (TCM)
• Software issues within the ECM

DTC C1170 seriousness

DTC C1170 is considered a serious issue as it can affect the vehicle’s ability to shift gears properly. This can lead to unsafe driving conditions, increased wear on the transmission, and potential damage if not addressed promptly. It is essential to diagnose and repair this issue to ensure the vehicle operates safely and efficiently.

How to diagnose DTC C1170

To diagnose DTC C1170, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1170 code.
2. Inspect the PRNDL switch for any visible damage or wear.
3. Check the wiring and connectors for signs of corrosion or loose connections.
4. Test the PRNDL switch using a multimeter to ensure it is functioning correctly.
5. Examine the transmission control module for any faults or software issues.
6. Clear the code and perform a road test to see if the code reappears.

How to fix DTC C1170 step-by-step instructions

To fix DTC C1170, follow these steps:

1. Identify and replace any faulty PRNDL switch.
2. Repair or replace damaged wiring and connectors.
3. Ensure all connections are secure and free of corrosion.
4. If necessary, reprogram or replace the transmission control module.
5. Clear the DTC using an OBD-II scanner.
6. Test drive the vehicle to confirm that the issue is resolved and the code does not return.

How to erase DTC C1170

To erase DTC C1170, 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 reappear.

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