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 thinks the gears in the part that helps the car switch between two-wheel and four-wheel drive aren't working right.
The P279A code indicates that the transfer case gear ratio is not as expected when the vehicle is in high gear. This could be due to mechanical issues or sensor problems.
The transfer case is responsible for distributing power from the transmission to the front and rear axles in four-wheel or all-wheel drive vehicles. The P279A code is triggered when the Powertrain Control Module (PCM) detects an incorrect gear ratio in the high range of the transfer case. This can be caused by mechanical failure, sensor issues, or electrical faults.
• Check Engine Light is on
• Vehicle may not switch between two-wheel and four-wheel drive
• Unusual noises from the transfer case
• Faulty transfer case motor
• Defective transfer case control module
• Worn or damaged gears in the transfer case
Transfer Case: A part of the drivetrain that transfers power from the transmission to the front and rear axles.
PCM: Powertrain Control Module, the computer that controls the engine and transmission functions.
• Use an OBD-II scanner to confirm the code
• Inspect the transfer case for mechanical damage
• Check the transfer case motor and control module for faults
• Replace the transfer case motor
• Repair or replace the transfer case control module
• Repair or replace damaged gears in the transfer case
• OBD-II scanner
• Multimeter
• Socket set
$500 - $1500
Moderate
• Ford F-150
• Chevrolet Silverado
• Jeep Wrangler
• Regular maintenance of the transfer case
• Avoiding harsh driving conditions
• Checking for and addressing unusual noises promptly
Transmission/Transfer Case Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid using four-wheel drive until the issue is resolved
Check with your vehicle manufacturer; transfer case issues may be covered under powertrain warranty.
The P279A code has been reported in vehicles with high mileage or those frequently used in off-road conditions.
Moderate – While the vehicle may still be drivable, it is important to address the issue to prevent further damage.
Ignoring this code could lead to further mechanical damage and potentially unsafe driving conditions.
• Vehicle must be driven in both two-wheel and four-wheel drive modes
• Test on a flat, level surface
The transfer case is located between the transmission and the drive shafts, typically under the vehicle near the center.
Q: Can I drive with a P279A code?
A: It is possible to drive, but it is not recommended as it may cause further damage.
Q: How can I prevent a P279A code?
A: Regular maintenance and avoiding extreme driving conditions can help prevent this code.
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