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 computer in your car found a problem with the part that helps the car switch between different driving modes, like 2-wheel drive and 4-wheel drive.
The C12A5 code is set when the Transfer Case Control Module (TCCM) detects an issue with its classification or configuration.
The Transfer Case Control Module is responsible for controlling the transfer case, which allows the vehicle to switch between different drive modes. This code indicates that the TCCM has detected a problem with its classification data, which might be due to incorrect programming or faulty module communication.
• 4WD system not working
• Warning light on dashboard
• Unusual noises from the transfer case
• Faulty Transfer Case Control Module
• Incorrect module programming
• Poor electrical connection
TCCM: Transfer Case Control Module
4WD: Four-Wheel Drive
• Check for additional codes
• Inspect TCCM wiring and connectors
• Verify TCCM programming and configuration
• Reprogram or replace the TCCM
• Repair or replace damaged wiring
• Ensure proper module installation
• OBD-II scanner
• Multimeter
• Screwdriver set
$200 - $800
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regular maintenance of the 4WD system
• Ensure proper software updates
• Inspect electrical connections regularly
Control Module Issue
• Avoid using 4WD until the issue is resolved
• Consult a professional mechanic
• Do not ignore the warning light
Check with the vehicle manufacturer for warranty coverage related to control module issues.
This code has been reported in vehicles with electronic 4WD systems, often due to software or electrical issues.
Moderate – It affects the functionality of the 4WD system but may not impact immediate drivability.
Driving with a malfunctioning 4WD system can lead to vehicle instability. Ensure repairs are made promptly.
• Vehicle parked on a level surface
• Ignition in the 'On' position
The Transfer Case Control Module is usually located near the transfer case or under the dashboard.
Q: Can I drive with a C12A5 code?
A: It's not recommended to use the 4WD system until the issue is fixed, but the vehicle can still be driven in 2WD mode.
Q: Will resetting the code fix the problem?
A: Resetting the code may temporarily clear the warning, but the underlying issue needs to be addressed for a permanent fix.
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