Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble talking to the part that helps change gears. It's like when two friends can't hear each other on the phone because the line is bad.
The P085C code indicates a high voltage issue in the communication circuit for Gear Shift Control Module B, which can affect gear shifting operations.
The Gear Shift Control Module B is responsible for managing the gear shift operations in a vehicle. A 'Communication Circuit High' fault suggests that the voltage level in the communication line is higher than expected, which can disrupt the communication between the module and the vehicle's main computer.
• Check Engine Light is on
• Difficulty in shifting gears
• Transmission may not shift properly
• Unusual noises during gear shifts
• Faulty Gear Shift Control Module B
• Wiring issues such as short circuits or open circuits
• Poor electrical connections
• Faulty or damaged connectors
• Software issues in the vehicle's control system
OBD-II: On-Board Diagnostics, a standardized system for vehicle diagnostics.
Gear Shift Control Module: An electronic module that manages gear shifting operations.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Check the voltage levels in the communication circuit.
• Test the Gear Shift Control Module B for proper operation.
• Update or reprogram the vehicle's software if necessary.
• Repair or replace damaged wiring or connectors.
• Replace the Gear Shift Control Module B if faulty.
• Ensure all electrical connections are secure.
• Reprogram the vehicle's software if required.
• OBD-II Scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain wiring and connectors.
• Avoid exposure of electronic components to moisture.
• Ensure software updates are performed as recommended.
Communication Issue
• Do not ignore the Check Engine Light.
• Consult a professional mechanic for diagnosis.
• Avoid driving the vehicle extensively until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on electronic components.
This code has been reported in vehicles with complex electronic systems, particularly those with advanced transmission controls.
Moderate – It is advisable to address this issue soon to avoid potential transmission problems.
Driving with transmission issues can be unsafe. Ensure repairs are conducted by a qualified professional.
• Vehicle in park or neutral
• Engine running
The Gear Shift Control Module B is typically located near the transmission or within the vehicle's cabin, depending on the make and model.
Q: Can I drive my car with a P085C code?
A: It's not recommended to drive extensively with this code as it may lead to transmission issues.
Q: How do I reset the P085C code?
A: After repairs, you can reset the code using an OBD-II scanner, but ensure the issue is fixed first.
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