C1729 – OBD-II DTC

OBD-II DTC C1729 – Transfer Case unable to transition between 4H and 4L

DTC C1729 meaning

DTC C1729 indicates that the transfer case is unable to transition between 4H (four-wheel drive high) and 4L (four-wheel drive low) modes. This code is generated when the vehicle’s onboard diagnostic system detects a malfunction in the transfer case control system, which may prevent the driver from switching between these two modes effectively.

DTC C1729 symptoms

Common symptoms associated with DTC C1729 may include:

• Inability to shift from 4H to 4L or vice versa
• Warning lights illuminated on the dashboard
• Unusual noises from the transfer case
• Vehicle may remain stuck in one drive mode
• Poor traction or handling in off-road conditions

DTC C1729 causes

Several factors can lead to the occurrence of DTC C1729, including:

• Faulty transfer case control module
• Malfunctioning shift motor or actuator
• Wiring issues or poor connections in the transfer case circuit
• Low transfer case fluid levels or contamination
• Mechanical issues within the transfer case itself

DTC C1729 seriousness

DTC C1729 is considered a serious issue as it affects the vehicle’s ability to switch between drive modes. This can lead to:

• Reduced traction in adverse conditions
• Increased risk of getting stuck in off-road situations
• Potential damage to the transfer case if operated improperly

How to diagnose DTC C1729

To diagnose DTC C1729, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1729 code.
2. Inspect the transfer case control module for any visible damage or corrosion.
3. Check the wiring and connectors for any signs of wear or poor connections.
4. Test the shift motor or actuator for proper operation.
5. Verify the transfer case fluid level and condition.
6. Perform a functional test of the transfer case to see if it can shift between modes.

How to fix DTC C1729 step-by-step instructions

To fix DTC C1729, follow these steps:

1. Inspect and repair any damaged wiring or connectors related to the transfer case.
2. Replace the transfer case control module if it is found to be faulty.
3. Repair or replace the shift motor or actuator if it is malfunctioning.
4. Ensure the transfer case fluid is at the correct level and replace it if contaminated.
5. Clear the DTC using an OBD-II scanner and test drive the vehicle to ensure the issue is resolved.

How to erase DTC C1729

To erase DTC C1729, 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 codes.
5. Disconnect the scanner and start the vehicle to check if the code returns.

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