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 getting a signal that's too high from a switch that helps the car know if it's in drive mode.
The P0855 code is triggered when the Powertrain Control Module (PCM) detects a high voltage signal from the drive switch input circuit, which is outside the expected range.
The drive switch input circuit is responsible for communicating the current gear selection to the vehicle's PCM. A 'high' signal indicates that the voltage level is above the expected threshold, which could be due to a short circuit, faulty switch, or wiring issues.
• Check engine light is on
• Transmission may not shift correctly
• Vehicle may not go into drive mode
• Faulty drive mode switch
• Short circuit in the wiring
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the drive switch and its wiring for damage.
• Test the voltage at the drive switch.
• Replace the drive mode switch if faulty.
• Repair or replace damaged wiring.
• Check and possibly replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regularly inspect wiring for wear and tear.
• Ensure all connectors are secure.
• Conduct routine vehicle diagnostics.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult with a professional mechanic for accurate diagnosis.
Check if the vehicle's powertrain warranty covers electrical components.
This code has been associated with vehicles experiencing transmission issues due to electrical faults.
Moderate – Should be addressed soon to avoid transmission issues.
Ignoring this issue could lead to unsafe driving conditions. Always ensure your vehicle is in good working order.
• Vehicle in park
• Engine running
The drive switch is typically located near the gear shifter or integrated within the transmission control module.
Q: Can I drive with a P0855 code?
A: It's not recommended as it may lead to transmission issues.
Q: How do I clear the P0855 code?
A: Fix the underlying issue and use an OBD-II scanner to clear the code.
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