Why do I get code c0379 on my Silverado Sierra?
When the TCCM grounds the light blue wire the actuator locks the axle. If either circuit is open, grounded, or shorted to voltage you will get that code. Fast test: Key ON engine OFF and 2WD selected use a meter from battery ground to test for 12V at the brown wire, then the light blue wire.
What is the c0379 control circuit all about?
Re: C0379 Help! C0379 is all about the axle actuator control circuit. Should be 12V on the brown wire at the actuator, and the TCCM should see 12V coming through the actuator on the light blue wire. When the TCCM grounds the light blue wire the actuator locks the axle.
When to use the 4WD service code c0379?
This condition may only occur after a cold temperature start-up (typically below -6°C to -1°C (20°F to 30°F). If this concern is accompanied by an illuminated “Service 4WD” light, and a DTC C0379, during a cold weather start up, the following information may apply.
When to use the c0379 history code?
Important: When a vehicle with this concern is diagnosed in the repair facility, usually the inside temperature is warm enough that the system operates normally, and the C0379 will be set as a history code, making the concern intermittent and difficult to diagnose.
When the TCCM grounds the light blue wire the actuator locks the axle. If either circuit is open, grounded, or shorted to voltage you will get that code. Fast test: Key ON engine OFF and 2WD selected use a meter from battery ground to test for 12V at the brown wire, then the light blue wire.
How much does it cost to diagnose a c0379 code?
The cost of diagnosing the C0379 code is 1.0 hour of labor. The auto repair’s diagnosis time and labor rates vary by location, vehicle’s make and model, and even your engine type.
This condition may only occur after a cold temperature start-up (typically below -6°C to -1°C (20°F to 30°F). If this concern is accompanied by an illuminated “Service 4WD” light, and a DTC C0379, during a cold weather start up, the following information may apply.
Important: When a vehicle with this concern is diagnosed in the repair facility, usually the inside temperature is warm enough that the system operates normally, and the C0379 will be set as a history code, making the concern intermittent and difficult to diagnose.