B1629 – OBD-II DTC

OBD-II DTC B1629 – PRNDL Reverse Input Short To Battery

DTC B1629 meaning

DTC B1629 refers to a diagnostic trouble code indicating a “PRNDL Reverse Input Short To Battery.” This code is generated when the vehicle’s onboard diagnostic system detects a short circuit in the reverse input circuit of the PRNDL (Park, Reverse, Neutral, Drive, Low) switch, which is responsible for indicating the transmission’s gear position. A short to battery means that the circuit is receiving an unexpected voltage, which can lead to incorrect gear position readings.

DTC B1629 symptoms

Common symptoms associated with DTC B1629 may include:

• Illumination of the check engine light
• Transmission not shifting properly
• Inability to engage reverse gear
• Erratic or incorrect gear position display on the dashboard
• Potential stalling or engine performance issues

DTC B1629 causes

Several factors can lead to the occurrence of DTC B1629, including:

• Faulty PRNDL switch
• Wiring issues, such as damaged or frayed wires
• Corrosion or poor connections in the electrical circuit
• Short circuit in the reverse input circuit
• Faulty transmission control module (TCM)

DTC B1629 seriousness

DTC B1629 can be considered serious as it affects the vehicle’s transmission functionality. If left unaddressed, it may lead to:

• Inability to safely operate the vehicle
• Increased risk of accidents due to transmission failure
• Potential damage to the transmission system

How to diagnose DTC B1629

To diagnose DTC B1629, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC B1629.
2. Inspect the PRNDL switch for any visible damage or wear.
3. Check the wiring and connectors for signs of corrosion or damage.
4. Test the PRNDL switch for proper operation using a multimeter.
5. Examine the transmission control module for faults or issues.
6. Clear the code and perform a road test to see if the code reappears.

How to fix DTC B1629 step-by-step instructions

To fix DTC B1629, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect and repair any damaged wiring or connectors related to the PRNDL switch.
3. Replace the PRNDL switch if it is found to be faulty.
4. Reconnect the battery and clear the DTC using an OBD-II scanner.
5. Perform a road test to verify that the issue has been resolved.

How to erase DTC B1629

To erase DTC B1629, 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 return.

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