Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble talking to a switch that helps control how the car shifts gears.
The P071C code indicates that the transmission control module (TCM) has detected a high voltage condition in the circuit of the transmission mode switch 'A'.
This code is triggered when the TCM detects a voltage level that is higher than expected in the transmission mode switch 'A' circuit. This switch is responsible for sending signals to the TCM about the current gear mode, and a high voltage condition could indicate a short circuit or a faulty switch.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may go into limp mode
• Faulty transmission mode switch
• Wiring issues such as a short circuit
• Faulty transmission control module (TCM)
Transmission Control Module (TCM): A computer that controls the transmission functions.
OBD-II: On-Board Diagnostics, a system for self-diagnosing and reporting vehicle issues.
• Use an OBD-II scanner to confirm the code.
• Inspect the transmission mode switch and its wiring for damage.
• Test the voltage and continuity of the circuit.
• Replace the faulty transmission mode switch.
• Repair or replace damaged wiring.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect transmission wiring.
• Ensure proper maintenance of the transmission system.
• Avoid harsh driving conditions.
Sensor Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for a proper diagnosis.
Check with your vehicle manufacturer for warranty coverage related to the transmission system.
This code has been associated with transmission issues in various models, often related to wiring problems or switch failures.
Moderate – Should be addressed soon to avoid transmission damage.
Driving with a faulty transmission can be unsafe and may lead to further vehicle damage.
• Vehicle must be in park or neutral.
• Engine should be running.
The transmission mode switch is typically located on the transmission housing or near the gear shifter.
Q: Can I drive with a P071C code?
A: It's not recommended as it may lead to transmission damage or unsafe driving conditions.
Q: How can I reset the P071C code?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
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