Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a switch that tells it what mode the transmission should be in, like drive or reverse. This code means there's a problem with the electrical part of that switch.
The transmission mode switch sends signals to the car's computer to indicate the selected gear. A 'circuit low' code means the signal is weaker than expected.
P071B is triggered when the powertrain control module (PCM) detects a low voltage signal from the transmission mode switch A circuit, indicating a potential electrical issue or fault in the switch or its wiring.
• Check Engine Light is on
• Transmission stuck in one gear
• Erratic shifting
• Faulty transmission mode switch
• Damaged wiring or connectors
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Check for additional trouble codes.
• Inspect the transmission mode switch and its wiring for damage.
• Test the voltage and ground signals at the switch.
• Replace the transmission mode switch if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance and inspection of transmission components.
• Ensure proper electrical connections.
• Avoid harsh driving conditions.
Sensor Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with vehicles experiencing electrical issues in the transmission control system.
Moderate – Should be addressed soon to avoid potential transmission damage.
Driving with a malfunctioning transmission can lead to safety issues. Address the problem promptly.
• Vehicle is in park or neutral.
• Engine is running.
The transmission mode switch is typically located on the transmission housing or gear selector assembly.
Q: Can I drive with a P071B code?
A: It's not recommended to drive with this code as it may lead to transmission damage.
Q: How can I reset the P071B code?
A: You can reset the code using an OBD-II scanner, but ensure the issue is fixed to prevent it from returning.
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