AutoCodes – Generic – C0406

C0406 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 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 1,516

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

What does this mean?

What are the Possible Causes of the DTC C0406?

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?

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 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 code?

Need more information on how to fix the C0406 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the C0406 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

C0406 Buick — Transfer Case Solenoid Valve Control Circuit High Current
C0406 Cadillac — Transfer Case Solenoid Valve Control Circuit High Current
C0406 Chevrolet — Transfer Case Solenoid Valve Control Circuit High Current
C0406 GMC — Transfer Case Solenoid Valve Control Circuit High Current

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 Code

1. What does the OBDII code C0406 mean?

C0406 indicates a problem with the transfer case solenoid valve control circuit, specifically that it is experiencing abnormally high current.

2. What are the common symptoms of a C0406 code?

Symptoms may include the all-wheel drive (AWD) or four-wheel drive (4WD) system not engaging properly, warning lights on the dashboard, or unusual noises from the transfer case.

3. What causes the C0406 code to appear?

Common causes include a short circuit in the wiring, a faulty transfer case solenoid valve, a damaged control module, or corroded electrical connections.

4. Can I drive my vehicle with a C0406 code?

While the vehicle may still be drivable, the AWD or 4WD system may not function properly, which could be dangerous in certain driving conditions. Itâ€™s best to address the issue promptly.

5. How is the C0406 code diagnosed?

A technician will inspect the wiring and connectors for damage, test the transfer case solenoid valve for proper operation, and use a scan tool to monitor the circuit's voltage and current.

6. How can I fix the C0406 code?

Repairs may include replacing a damaged transfer case solenoid valve, repairing or replacing damaged wiring, cleaning corroded connectors, or reprogramming or replacing the control module if needed.

7. What tools are needed to diagnose the C0406 code?

Youâ€™ll typically need an OBDII scanner, a multimeter to test electrical circuits, and potentially wiring diagrams to trace the circuit.

8. Does the C0406 code require a software update?

In some cases, a software update to the vehicleâ€™s control module may resolve the issue, but this depends on the manufacturer and specific circumstances.

9. How much does it cost to repair a C0406 code?

The cost can vary widely depending on the root cause, ranging from $100 for simple wiring repairs to over $500 if the solenoid or control module needs replacement.

10. Can a C0406 code clear itself?

The code may temporarily clear if the issue is intermittent, but it is likely to return until the underlying problem is repaired.