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 is having trouble understanding the signal from the part that controls how the 4-wheel drive system switches between different modes.
The P279E code is triggered when the vehicle's powertrain control module (PCM) detects a problem with the signal from the 4WD range switch, which is responsible for indicating the current range or mode of the 4WD system.
The 4WD range signal circuit is responsible for sending information about the 4WD system's current mode (such as high or low range) to the vehicle's PCM. If the signal is out of the expected range or performance parameters, the PCM will set the P279E code.
• 4WD system not engaging properly
• 4WD warning light illuminated
• Unusual noises from the 4WD system
• Faulty 4WD range switch
• Damaged wiring or connectors in the 4WD range circuit
• Malfunctioning PCM
PCM: Powertrain Control Module
4WD: Four-Wheel Drive
• Inspect the 4WD range switch and its wiring for damage.
• Check for loose or corroded connectors in the 4WD circuit.
• Test the 4WD range switch for proper operation using a multimeter.
• Replace the faulty 4WD range switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$150 - $500
Moderate
• Toyota Tacoma
• Ford F-150
• Jeep Wrangler
• Regularly inspect 4WD system components.
• Keep connectors clean and free from corrosion.
• Perform scheduled maintenance on the 4WD system.
Sensor Issue
• Avoid using 4WD until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle's manufacturer for warranty coverage on drivetrain components.
This code has become more common with the increased use of electronic 4WD systems in modern vehicles.
Moderate – It's important to address this issue to ensure proper 4WD functionality.
Driving with a malfunctioning 4WD system can lead to loss of vehicle control in certain conditions.
• Vehicle must be in 4WD mode.
• Drive on a surface where 4WD is needed to replicate the issue.
The 4WD range switch is typically located on the transfer case of the vehicle.
Q: Can I drive my vehicle with the P279E code?
A: It's best to avoid using 4WD until the issue is fixed, as it can lead to further damage.
Q: How can I reset the P279E code?
A: After repairs, the code can be cleared using an OBD-II scanner.
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