Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The computer that helps your car switch between two-wheel drive and four-wheel drive is getting too hot.
The transfer case control module monitors the temperature of the transfer case and ensures it operates within a safe range. If the temperature exceeds the safe limit, this code is triggered.
The C12AB code indicates that the transfer case control module has detected an over-temperature condition. This could be due to excessive load, insufficient lubrication, or a malfunctioning cooling system.
• Warning light on the dashboard
• Difficulty in switching between drive modes
• Unusual noises from the transfer case
• Insufficient lubrication in the transfer case
• Faulty cooling system
• Excessive load on the transfer case
Transfer Case: A part of the drivetrain that transfers power from the transmission to the front and rear axles.
Control Module: An electronic device that controls various functions in the vehicle.
• Verify the code with an OBD-II scanner
• Inspect the transfer case for leaks or damage
• Check the cooling system for proper operation
• Refill or replace transfer case fluid
• Repair or replace the cooling system components
• Replace the transfer case control module if faulty
• OBD-II scanner
• Wrench set
• Thermal imaging camera
$200 - $800
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly check and change transfer case fluid
• Avoid overloading the vehicle
• Ensure cooling system is functioning properly
Temperature Sensor Issue
• Avoid driving in extreme conditions until fixed
• Regular maintenance checks
• Consult a professional mechanic if unsure
Check with vehicle manufacturer for specific warranty coverage related to drivetrain components.
This code has been more prevalent in vehicles used in off-road conditions or those with high towing loads.
Moderate – Address the issue soon to prevent further damage.
Ignoring this issue could lead to drivetrain failure, which may compromise vehicle safety.
• Vehicle in operation
• Transfer case engaged
The transfer case control module is typically located near the transfer case, under the vehicle.
Q: Can I drive with the C12AB code?
A: It's not recommended to drive for long periods with this code as it may cause further damage.
Q: How often should I check my transfer case fluid?
A: It's recommended to check the transfer case fluid every 30,000 miles or as specified in your vehicle's manual.
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