P0704 – OBD-II DTC

OBD-II DTC P0704 – Torque Converter/Brake Switch B Circuit Malfunction

DTC P0704 meaning

DTC P0704 refers to a malfunction in the Torque Converter/Brake Switch B Circuit. This code indicates that the vehicle’s onboard diagnostic system has detected an issue with the circuit that connects the torque converter clutch and the brake switch. The torque converter is responsible for transferring power from the engine to the transmission, while the brake switch signals when the brakes are applied. A malfunction in this circuit can affect the vehicle’s performance and transmission operation.

DTC P0704 symptoms

Common symptoms associated with DTC P0704 may include:

• Illuminated check engine light
• Transmission slipping or harsh shifting
• Reduced engine power
• Inability to engage or disengage the torque converter
• Unexpected engine stalling

DTC P0704 causes

Several factors can lead to the triggering of DTC P0704, including:

• Faulty brake switch
• Wiring issues or damaged connectors in the circuit
• Faulty torque converter clutch solenoid
• Transmission control module (TCM) malfunction
• Low transmission fluid levels or contamination

DTC P0704 seriousness

DTC P0704 can be considered serious as it may affect the vehicle’s drivability and safety. If the torque converter is not functioning correctly, it can lead to:

• Increased wear on the transmission
• Potential for stalling or loss of power while driving
• Difficulty in shifting gears

It is advisable to address this issue promptly to avoid further damage to the vehicle.

How to diagnose DTC P0704

To diagnose DTC P0704, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P0704 code.
2. Inspect the brake switch for proper operation and wiring integrity.
3. Check the torque converter clutch solenoid for functionality.
4. Examine the wiring and connectors in the Torque Converter/Brake Switch B circuit for damage or corrosion.
5. Test the transmission control module (TCM) for any faults.
6. Check the transmission fluid level and condition.

How to fix DTC P0704 step-by-step instructions

To fix DTC P0704, follow these steps:

1. Replace the faulty brake switch if it is not functioning correctly.
2. Repair or replace any damaged wiring or connectors in the circuit.
3. Replace the torque converter clutch solenoid if it is defective.
4. Reprogram or replace the transmission control module (if necessary).
5. Ensure the transmission fluid is at the correct level and is clean replace if contaminated.
6. Clear the DTC using an OBD-II scanner and test drive the vehicle to ensure the issue is resolved.

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