P279B Buick Code - Four Wheel Drive Low Range Performance
Quick Answer
The Engine Control Module (ECM) uses the following two ways to determine if the transfer case is in 4WD Low, 4WD High, or Neutral. Common causes include Reprogram Engine Control Module (ECM), Faulty Engine Control Module, Engine Control Module harness is open or shorted. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P279B Buick indicates Four Wheel Drive Low Range Performance .
- Common causes
- Common causes include Reprogram Engine Control Module (ECM), Faulty Engine Control Module, Engine Control Module harness is open or shorted.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P279B Buick Description
1. The first way is to compare the transmission output speed sensor to the transfer case output speed sensor in order to calculate the transfer case range.
2. The second way is to use a LAN message sent by the transfer case shift control module to the ECM.
The ECM uses this message to determine motor torque required and transmission shifting.
The internal fault detection is handled inside the control module. No external circuit diagnosis is involved.
If the first way and second way of determining transfer case range do not match while in 4WD Low, 4WD High or Neutral, then the Diagnostic Trouble Code (DTC) is set.
What are the Possible Causes of the DTC P279B Buick?
- Reprogram Engine Control Module (ECM)
- Faulty Engine Control Module
- Engine Control Module harness is open or shorted
- Engine Control Module circuit poor electrical connection
- Transmission internal mechanical problems
How to Fix the DTC P279B Buick?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P279B Buick code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P279B Buick Code
What does the OBDII code P279B mean for my Buick?
The P279B code indicates a Four Wheel Drive Low Range Performance issue, suggesting that the vehicle's four-wheel drive system is not performing as expected in low-range settings.
What are the common symptoms of a P279B code?
Common symptoms include difficulty engaging or disengaging the four-wheel drive, unusual noises from the transfer case, warning lights on the dashboard, and poor traction performance in low-range conditions.
What could cause the P279B code to trigger?
Causes may include faulty transfer case control module, worn or damaged transfer case components, low transmission fluid levels, or issues with the four-wheel drive actuator.
Is it safe to drive with a P279B code?
While it may be safe to drive, the vehicle may not perform well in off-road or slippery conditions due to compromised four-wheel drive functionality. It’s advisable to address the issue promptly.
How can I diagnose the P279B code?
Diagnosing the P279B code typically involves using an OBDII scanner to confirm the code, inspecting the transfer case and related components, checking fluid levels, and testing the four-wheel drive system.
What are some common repairs for a P279B code?
Common repairs may include reprogramming or replacing the transfer case control module, repairing or replacing the transfer case, and ensuring that all fluid levels are correct.
Can I reset the P279B code myself?
Yes, you can clear the code using an OBDII scanner, but it’s important to diagnose and resolve the underlying issue to prevent the code from returning.
Will clearing the P279B code fix the problem?
Clearing the code will only remove the code from the system temporarily. The underlying issue must be fixed to prevent the code from reappearing.
How much does it typically cost to repair a P279B code issue?
Repair costs can vary widely depending on the cause of the problem, ranging from minor repairs costing a few hundred dollars to more significant issues like a transfer case replacement, which could cost over a thousand dollars.
Discuss the causes and fixes for P279B Buick OBDII Code
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