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 thinks the gears in the part that changes how power is sent to the wheels (called the transfer case) are not working right when it's in neutral. It's like the car's brain is confused about what the gears are doing.
This code is triggered when the vehicle's powertrain control module (PCM) detects an incorrect gear ratio in the transfer case when it is supposed to be in neutral.
The P279C code indicates that the PCM has detected a gear ratio error in the transfer case while it is in the neutral position. The transfer case is responsible for distributing power from the transmission to the drive axles in vehicles with four-wheel or all-wheel drive systems. An incorrect ratio means that the expected gear ratio does not match the actual ratio being detected by the sensors.
• Check Engine Light illuminated
• Difficulty shifting between drive modes
• Unusual noises from the transfer case
• Faulty transfer case control module
• Malfunctioning transfer case shift motor
• Defective transfer case position sensor
Transfer Case: A component in four-wheel and all-wheel drive vehicles that distributes power from the transmission to the drive axles.
PCM: Powertrain Control Module, the vehicle's main computer that controls engine and transmission functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the transfer case wiring and connectors for damage.
• Test the transfer case shift motor and position sensor for proper operation.
• Replace the transfer case control module if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the transfer case shift motor or position sensor if defective.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Ford F-150
• Chevrolet Silverado
• Jeep Grand Cherokee
• Regular maintenance of the transfer case.
• Ensure proper lubrication of transfer case components.
• Avoid aggressive driving that can stress the transfer case.
Drivetrain Issue
• Avoid driving in conditions that require four-wheel drive until repaired.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with your vehicle manufacturer to see if the transfer case components are covered under warranty.
This code has been associated with issues in vehicles with electronic transfer cases, especially in models with high mileage or heavy usage.
Moderate – It is advisable to address this issue soon to prevent further drivetrain damage.
Ignoring this code may lead to drivetrain damage or loss of four-wheel drive capability, which can be hazardous in certain driving conditions.
• Vehicle must be in neutral.
• Transfer case engaged in four-wheel drive mode.
The transfer case is located between the transmission and the drive axles, usually beneath the vehicle near the center.
Q: Can I drive my car with a P279C code?
A: It's not recommended to drive extensively with this code, as it may lead to further damage. Consult a mechanic as soon as possible.
Q: What happens if I ignore the P279C code?
A: Ignoring this code can lead to drivetrain damage and may result in losing four-wheel drive functionality, which can be dangerous in certain conditions.
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