AutoCodes – GMC – C0307 GMC

C0307 GMC Code - Motor A/B Circuit Range/Performance

Quick Answer

The transfer case motor is a bi-directional, permanent magnet, D.C. Common causes include Faulty Transfer Case Motor, Transfer Case Motor harness is open or shorted, Transfer Case Motor 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: C0307 GMC indicates Motor A/B Circuit Range/Performance.
Common causes: Common causes include Faulty Transfer Case Motor, Transfer Case Motor harness is open or shorted, Transfer Case Motor 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.

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Code Popularity 949

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 18, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C0307 GMC Description

The transfer case motor is a bi-directional, permanent magnet, D.C. motor. When energized, (through Motor Control A or Motor Control B, the ground is provided by the opposing Motor Control circuit and then grounded through the transfer case shift control module ground circuit), the motor, through a series of gears, rotates a shaft which moves the mode and range forks to shift the transfer case between 4H, AUTO 4WD, 2H, N, and 4L ranges. While the transfer case motor is energized the transfer case shift control module also energizes the solenoid for the transfer case lock. The motor lock is disabled (locking action released) and free turning of the transfer case motor and sector shaft is then allowed.
This DTC detects a short to ground in Motor Control A or Motor Control B CKT.

OBDII Code C0307 GMC - Motor A/B Circuit Range/Performance - AutoCodes.com — C0307 GMC Code - Motor A/B Circuit Range/Performance

What does this mean?

What are the Possible Causes of the DTC C0307 GMC?

Faulty Transfer Case Motor
Transfer Case Motor harness is open or shorted
Transfer Case Motor circuit poor electrical connection

How to Fix the DTC C0307 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 C0307 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.

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about C0307 GMC Code

1. What are the common symptoms of OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- Common symptoms include rough idling, poor engine performance, hesitation during acceleration, and illuminated Check Engine Light.

2. What are the possible causes of OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- Possible causes may include a faulty motor assembly, wiring issues, loose connections, or a malfunctioning control module.

3. How can I diagnose the source of OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- Diagnosing this code typically involves inspecting the motor assembly, checking for loose or damaged wiring, and using a scan tool to analyze the control module data.

4. Can I drive my vehicle with OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- It is not recommended to drive your vehicle with this code active, as it can lead to further damage and potential safety issues. It's best to address the issue promptly.

5. How can I repair OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- Repair options may include replacing the motor assembly, repairing any damaged wiring, ensuring all connections are secure, and resetting the fault codes with a scan tool.

6. What tools are needed to diagnose and repair OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- Tools commonly needed include a scan tool for code reading and clearing, a multimeter for electrical testing, and basic hand tools for accessing and inspecting components.

7. Is OBDII code C0307 GMC Motor A/B Circuit Range/Performance a common issue in GMC vehicles?

- While not as common as some other codes, C0307 can occur in GMC vehicles, particularly in models with motor-driven components that may experience range or performance issues.

8. How much does it typically cost to repair OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- The cost of repairs can vary depending on the specific issue causing the code, but it may range from a few hundred to over a thousand dollars, including parts and labor.

9. Are there any preventive maintenance tips to avoid OBDII code C0307 GMC Motor A/B Circuit Range/Performance?

- Regularly inspecting and maintaining motor assemblies, checking wiring for damage, and addressing any performance issues promptly can help prevent this code from occurring.

10. Can OBDII code C0307 GMC Motor A/B Circuit Range/Performance be a DIY repair, or should it be done by a professional mechanic?

- While some aspects of diagnosing and repairing this code may be DIY-friendly, it's recommended to consult with a professional mechanic, especially for complex issues involving control modules or specialized tools.