Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of the car that tells the transmission how to work, like switching between different driving modes.
The P071D code indicates an issue with the transmission mode switch circuit, specifically circuit B. This switch helps the car's transmission know which mode it should be in, like park, drive, or reverse.
The Transmission Mode Switch B Circuit is responsible for sending signals to the vehicle's transmission control module (TCM) to indicate the current gear selection or mode. A fault in this circuit can cause incorrect mode selection or transmission operation.
• Transmission not shifting correctly
• Check Engine Light illuminated
• Vehicle stuck in one gear
• Faulty transmission mode switch
• Damaged wiring or connectors in the circuit
• Malfunctioning transmission control module (TCM)
Transmission Mode Switch: A component that helps the transmission control module determine the gear or mode the vehicle is in.
Transmission Control Module (TCM): An electronic device that manages the operation of the transmission.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the transmission mode switch for proper operation.
• Replace the faulty transmission mode switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect transmission wiring.
• Ensure connectors are clean and secure.
• Perform scheduled transmission maintenance.
Transmission Issue
• Avoid driving long distances until repaired.
• Have the vehicle inspected by a professional mechanic.
• Monitor for changes in transmission behavior.
Check if the vehicle's powertrain warranty covers transmission components.
This code has been associated with transmission mode switch issues in various models, often due to wear or environmental factors affecting electrical connections.
Moderate – It should be addressed soon to prevent further transmission issues.
Driving with a malfunctioning transmission can be unsafe and may cause further damage to the vehicle.
• Vehicle in park or neutral.
• Engine running at idle.
The transmission mode switch is typically located on the side of the transmission or near the gear shifter.
Q: What happens if I ignore the P071D code?
A: Ignoring this code can lead to transmission problems, making your vehicle unsafe to drive and potentially causing more costly repairs.
Q: Can I fix the P071D code myself?
A: If you have experience with car repairs, you might be able to fix it by checking the wiring and replacing the switch, but it's often best to consult a mechanic.
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