C0379 GMC Code - Front Axle Switch Circuit
Quick Answer
The front axle control circuit consists of an electric motor actuator that engages and disengages the front axle. Common causes include Faulty Front Axle Engagement Actuator, Front Axle Engagement Actuator harness is open or shorted, Front Axle Engagement Actuator circuit poor electrical connection. 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
- C0379 GMC indicates Front Axle Switch Circuit.
- Common causes
- Common causes include Faulty Front Axle Engagement Actuator, Front Axle Engagement Actuator harness is open or shorted, Front Axle Engagement Actuator circuit poor electrical connection.
- 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 C0379 GMC Description
The front axle engagement actuator contains the following circuits: A Run/Crank Ignition 1 Voltage circuit, a Four-Wheel Drive Wheel Lock Indicator circuit, a Front Axle Actuator Control circuit, and a ground circuit.
When a shift to 4WD Auto, 4WD High, or 4WD Low is requested, the Transfer Case Control Module engages the front axle by grounding the front axle actuator control circuit through a current limiting driver.
This Diagnostic Trouble Code (DTC) will be set when a short to ground, short to voltage, or open circuit is detected.
What are the Possible Causes of the DTC C0379 GMC?
- Faulty Front Axle Engagement Actuator
- Front Axle Engagement Actuator harness is open or shorted
- Front Axle Engagement Actuator circuit poor electrical connection
- Faulty Transfer Case Control Module
How to Fix the DTC C0379 GMC?
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 C0379 GMC 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.
Need more information about the C0379 GMC code?
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Information for Specific GMC Models
- C0379 2014 GMC Sierra — Front Axle Switch Circuit
- C0379 2015 GMC Sierra — Front Axle Switch Circuit
- C0379 2016 GMC Sierra — Front Axle Switch Circuit
- C0379 2017 GMC Sierra — Front Axle Switch Circuit
- C0379 2018 GMC Sierra — Front Axle Switch Circuit
Frequently Asked Questions about C0379 GMC Code
1. What are the common symptoms of OBDII code C0379 GMC (Front Axle Switch Circuit)?
The common symptoms of code C0379 include the service 4WD light illuminating on the dashboard, difficulty shifting into 4WD mode, or complete loss of 4WD functionality.
2. What are the possible causes of OBDII code C0379 GMC?
Possible causes of code C0379 include a faulty front axle switch, damaged wiring or connectors in the front axle switch circuit, or a malfunctioning transfer case control module.
3. How can I diagnose OBDII code C0379 GMC?
Diagnosing code C0379 typically involves using a scan tool to retrieve the code, checking the front axle switch for proper operation, inspecting the wiring and connectors for damage, and testing the transfer case control module for faults.
4. Can a DIY enthusiast repair OBDII code C0379 GMC?
While some DIY enthusiasts may be able to diagnose and repair code C0379, it is recommended to have a professional technician perform the diagnosis and repair due to the complexity of the electrical components involved.
5. What are the repair options for OBDII code C0379 GMC?
Repair options for code C0379 may include replacing the front axle switch, repairing or replacing damaged wiring or connectors, or reprogramming the transfer case control module.
6. Is it safe to continue driving with OBDII code C0379 GMC?
It is not recommended to continue driving with OBDII code C0379, as it can lead to loss of 4WD functionality, which may affect the vehicle's performance and safety, especially in adverse driving conditions.
7. How much does it typically cost to repair OBDII code C0379 GMC?
The cost of repairing OBDII code C0379 can vary depending on the specific cause of the issue, the cost of parts, and the labor rates of the repair shop. It is advisable to obtain quotes from different repair facilities.
8. Can extreme weather conditions trigger OBDII code C0379 GMC?
Extreme weather conditions such as water exposure or extreme cold can potentially cause damage to the front axle switch or wiring, leading to the triggering of code C0379.
9. Will resetting the OBDII system clear code C0379 GMC?
Resetting the OBDII system may temporarily clear the code, but if the underlying issue causing code C0379 is not addressed, the code is likely to reappear once the system detects the problem again.
10. Can a weak battery cause OBDII code C0379 GMC to trigger?
A weak or failing battery can potentially cause electrical issues that may lead to OBDII code C0379 triggering. It is recommended to ensure the battery is in good condition when diagnosing this code.
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