P279A GMC - Four Wheel Drive High Range Performance

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
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P279A GMC Possible Causes

  • Faulty Engine Control Module (ECM)
  • Engine Control Module (ECM) harness is open or shorted
  • Engine Control Module (ECM) circuit poor electrical connection

First diagnose P279A GMC code

    Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.

Cost of diagnosing the P279A GMC code

    Labor: 1.0

    The cost of diagnosing the P279A GMC code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

P279A GMC Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P279a Gmc Description

The Engine Control Module (ECM) uses the following two ways to determine if the transfer case is in 4WD Low, 4WD High or Neutral.

1. The first way is to compare the transmission output speed sensor to the transfer case output speed sensor in order to calculate 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.

OBDII Code P279a Gmc - Four Wheel Drive High Range Performance - AutoCodes.com

P279A GMC More Information

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P279A GMC Comments

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