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 a part that helps control the gears. It's like when two friends are trying to talk, but one can't hear the other very well.
The vehicle's powertrain control module (PCM) detects a low voltage or poor communication in the circuit that connects to the Gear Shift Control Module B.
The P085B code is triggered when the PCM identifies a low voltage or communication issue in the circuit responsible for the Gear Shift Control Module B. This module is part of the transmission system that helps manage gear shifting electronically.
• Check Engine Light illuminated
• Difficulty shifting gears
• Transmission stuck in one gear
• Faulty Gear Shift Control Module B
• Damaged wiring or connectors in the communication circuit
• Faulty PCM
PCM: Powertrain Control Module
ECU: Electronic Control Unit
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors related to the Gear Shift Control Module B.
• Test the Gear Shift Control Module B for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the Gear Shift Control Module B if faulty.
• Update or reprogram the PCM if necessary.
• OBD-II Scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regularly inspect and maintain vehicle wiring.
• Ensure connectors are clean and secure.
• Avoid harsh driving conditions that may damage electrical components.
Communication Circuit Issue
• Avoid driving the vehicle until the issue is fixed to prevent further damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on transmission and electronic components.
This code has been associated with communication issues in electronic transmission systems, particularly in vehicles with advanced gear control modules.
Moderate – It is advisable to address this issue soon to avoid potential transmission problems.
Driving with a faulty transmission can be unsafe. Address this issue promptly to ensure vehicle safety.
• Vehicle in park or neutral
• Engine running
The Gear Shift Control Module B is typically located near the transmission or integrated within the vehicle's electronic control unit (ECU).
Q: Can I drive with a P085B code?
A: It's not recommended to drive with this code as it can lead to transmission issues.
Q: How can I prevent this code from appearing?
A: Regular maintenance and inspection of the vehicle's electrical systems can help prevent this issue.
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