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's a problem with the computer that controls the part of the car that switches between two-wheel and four-wheel drive.
The Transfer Case Control Module (TCCM) is responsible for controlling the transfer case, which determines whether the vehicle operates in two-wheel drive or four-wheel drive mode. A performance issue indicates that the module is not functioning as expected.
The C12AF code is set when the Transfer Case Control Module (TCCM) detects a malfunction in its performance. This could be due to electrical issues, software glitches, or mechanical problems within the transfer case system.
• Unable to switch between two-wheel and four-wheel drive
• Warning light on the dashboard
• Unusual noises from the transfer case
• Faulty Transfer Case Control Module
• Electrical wiring issues
• Software malfunction
Transfer Case: A part of the drivetrain that transfers power from the transmission to the front and rear axles.
Control Module: An electronic component that manages specific functions in a vehicle.
• Check for any additional codes that might indicate related issues.
• Inspect the wiring and connectors to the TCCM for damage or corrosion.
• Test the TCCM using a diagnostic scan tool.
• Repair or replace damaged wiring or connectors.
• Reprogram or update the TCCM software.
• Replace the Transfer Case Control Module if faulty.
• OBD-II scanner
• Multimeter
• Basic hand tools
$300 - $800
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly inspect and maintain the transfer case system.
• Ensure software updates are applied promptly.
• Avoid harsh driving conditions that may stress the transfer case.
Control Module Performance
• Have the vehicle inspected by a professional if you notice any symptoms.
• Avoid using four-wheel drive until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on the TCCM.
This code has been reported in vehicles with electronic transfer case systems, particularly in models with higher mileage.
Moderate – It is advisable to address this issue soon to avoid potential drivetrain damage.
Ignoring this issue may lead to loss of vehicle control in certain driving conditions.
• Vehicle stationary
• Ignition in the 'On' position
The Transfer Case Control Module is typically located near the transfer case or under the dashboard.
Q: Can I drive my car with this code?
A: It's possible to drive, but it's recommended to have it inspected soon to prevent further issues.
Q: Will this code affect my fuel efficiency?
A: It might, especially if the vehicle is stuck in four-wheel drive mode.
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