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 is a problem with the switch that tells the car's computer what gear the transmission should be in. It's like when a light switch in your house doesn't work properly.
The Transmission Mode Switch A Circuit is responsible for sending signals to the vehicle's computer to indicate the current gear selection. This code is triggered when there is an issue with the circuit that the switch uses to communicate.
The P071A code is set when the powertrain control module (PCM) detects a malfunction in the transmission mode switch circuit. This could be due to electrical issues such as a short or open circuit, or a failure in the switch itself. The transmission mode switch, sometimes referred to as a gear selector switch, is crucial for ensuring the transmission operates in the correct mode.
• Check Engine Light illuminated
• Transmission may not shift properly
• Vehicle may be stuck in a single gear
• Reduced fuel efficiency
• Faulty transmission mode switch
• Open or shorted wiring in the transmission mode switch circuit
• Poor electrical connection at the transmission mode switch
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the transmission mode switch for damage.
• Check the wiring and connectors for signs of wear or corrosion.
• Test the switch and circuit for proper operation using a multimeter.
• Replace the faulty transmission mode switch.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Screwdrivers and wrenches
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain transmission components.
• Avoid harsh driving conditions that can damage the transmission.
• Ensure the vehicle's electrical system is in good condition.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult with a professional mechanic for accurate diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on transmission components.
The P071A code has been associated with transmission issues in various vehicle models, often linked to electrical problems within the transmission system.
Moderate – While the vehicle may still be drivable, it is important to address this issue to avoid potential transmission damage.
Driving with a malfunctioning transmission can be dangerous and may lead to further mechanical failures.
• Vehicle in park or neutral
• Engine running
The transmission mode switch is typically located on the transmission itself, near the gear selector mechanism.
Q: Can I drive with a P071A code?
A: It's not recommended to drive with this code active, as it can lead to transmission damage or unsafe driving conditions.
Q: How do I clear a P071A code?
A: After repairing the issue, use an OBD-II scanner to clear the code from the vehicle's computer.
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