AutoCodes – GMC – C0406 GMC

C0406 GMC Code - Transfer Case Solenoid Valve Control Circuit High Current

Quick Answer

The rear drive clutch solenoid valve is internal to the torque transfer device housing. Common causes include Faulty Transfer Case Solenoid Valve, Transfer Case Solenoid Valve harness is open or shorted, Transfer Case Solenoid Valve 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: C0406 GMC indicates Transfer Case Solenoid Valve Control Circuit High Current.
Common causes: Common causes include Faulty Transfer Case Solenoid Valve, Transfer Case Solenoid Valve harness is open or shorted, Transfer Case Solenoid Valve 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 758

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 Jul 04, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C0406 GMC Description

The rear drive clutch solenoid valve is internal to the torque transfer device housing. The rear differential clutch control module supplies battery voltage to the control circuit and ground to the low reference circuit of the solenoid valve. The solenoid valve is controlled by a pulse width modulation (PWM) signal. The solenoid valve controls the hydraulic pressure to the clutch package of the torque transfer device. The locking level of the torque transfer device depends on the engagement of the clutch package.

OBDII Code C0406 GMC - Transfer Case Solenoid Valve Control Circuit High Current - AutoCodes.com — C0406 GMC Code - Transfer Case Solenoid Valve Control Circuit High Current

What does this mean?

What are the Possible Causes of the DTC C0406 GMC?

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

How to Fix the DTC C0406 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 C0406 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 C0406 GMC code?

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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 C0406 GMC Code

1. What are the common symptoms of OBDII code C0406 GMC?

- Common symptoms include the Service 4WD light illuminating on the dashboard, erratic shifting of the transfer case, and difficulty engaging 4WD.

2. What could cause the OBDII code C0406 GMC to appear?

- The code C0406 typically indicates a high current condition in the transfer case solenoid valve control circuit, which can be caused by a faulty solenoid, damaged wiring, or a poor connection.

3. How can I diagnose the cause of OBDII code C0406 GMC?

- A thorough diagnosis involves checking the transfer case solenoid valve, inspecting the wiring harness for damage, and testing the electrical connections for proper voltage and continuity.

4. Is it safe to continue driving my vehicle with the OBDII code C0406 GMC present?

- It is not recommended to continue driving with the code present, as it can lead to further damage to the transfer case and potentially compromise the vehicle's ability to engage 4WD.

5. Can I repair OBDII code C0406 GMC myself?

- While some DIY enthusiasts may attempt to repair this code themselves by replacing the transfer case solenoid valve or repairing damaged wiring, it is recommended to seek professional help for an accurate diagnosis and proper repair.

6. How much does it typically cost to repair OBDII code C0406 GMC?

- The cost of repairing OBDII code C0406 can vary depending on the underlying cause, but it may range from $200 to $600, including parts and labor.

7. Are there any preventive maintenance tips to avoid OBDII code C0406 GMC?

- Regularly inspecting and maintaining the transfer case components, such as the solenoid valve and wiring, can help prevent issues that may trigger the C0406 trouble code.

8. Can weather conditions affect the occurrence of OBDII code C0406 GMC?

- Extreme weather conditions, such as exposure to water or corrosive road salt, can contribute to the development of electrical issues in the transfer case solenoid valve control circuit, leading to the code C0406.

9. Will resetting the trouble codes make OBDII code C0406 GMC disappear permanently?

- Simply clearing the trouble codes may temporarily remove the C0406 code, but if the underlying issue is not addressed and repaired, the code is likely to reappear upon driving the vehicle.

10. Is it necessary to address OBDII code C0406 GMC immediately?

- It is advisable to address the OBDII code C0406 promptly to prevent further damage to the transfer case components and ensure the proper functioning of the 4WD system.