Four Wheel Drive Low Range Performance
Table of contents
P279B CADILLAC Possible Causes
- Faulty Engine Control Module (ECM)
- Engine Control Module (ECM) harness is open or shorted
- Engine Control Module (ECM) circuit poor electrical connection
How do I fix code P279B CADILLAC?
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 connector’s pins.
Cost of diagnosing the P279B CADILLAC code
The cost of diagnosing the P279B CADILLAC 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.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P279B CADILLAC 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.