P0720 – OBD-II DTC

OBD-II DTC P0720 – Torque Converter/Brake Switch B Circuit Low

DTC P0720 meaning

DTC P0720 refers to a diagnostic trouble code that indicates a problem with the Torque Converter/Brake Switch B Circuit. Specifically, it signifies that the vehicle’s powertrain control module (PCM) has detected a low voltage condition in the circuit associated with the torque converter or brake switch. This can affect the vehicle’s transmission performance and overall drivability.

DTC P0720 symptoms

Common symptoms associated with DTC P0720 may include:

• Illuminated check engine light
• Transmission slipping or erratic shifting
• Reduced engine performance
• Inability to engage or disengage the torque converter
• Unusual engine RPM fluctuations

DTC P0720 causes

Several factors can lead to the triggering of DTC P0720, including:

• Faulty torque converter or brake switch
• Wiring issues, such as shorts or open circuits
• Corroded or loose electrical connectors
• Faulty powertrain control module (PCM)
• Transmission fluid issues, such as low fluid levels or contamination

DTC P0720 seriousness

DTC P0720 can be considered serious as it may lead to transmission problems and affect vehicle safety. If left unaddressed, it can result in:

• Increased wear and tear on transmission components
• Potential for complete transmission failure
• Reduced fuel efficiency
• Compromised vehicle control

How to diagnose DTC P0720

To diagnose DTC P0720, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P0720 code.
2. Inspect the wiring and connectors related to the torque converter and brake switch for damage or corrosion.
3. Test the voltage at the brake switch and torque converter circuit to ensure it meets specifications.
4. Check for any additional trouble codes that may provide further insight into the issue.
5. Perform a visual inspection of the transmission fluid for contamination or low levels.

How to fix DTC P0720 step-by-step instructions

To fix DTC P0720, follow these step-by-step instructions:

1. Clear the DTC using an OBD-II scanner.
2. Inspect and repair any damaged wiring or connectors related to the torque converter and brake switch.
3. Replace the brake switch or torque converter if they are found to be faulty.
4. Ensure the transmission fluid is at the correct level and is clean replace if necessary.
5. Recheck the system by running the vehicle and monitoring for any reoccurrence of the DTC.

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