OBD Guide

C0402

Transfer Case Solenoid Valve

C0402 is an OBD-II diagnostic trouble code meaning: Transfer Case Solenoid Valve. Common causes: transfer case solenoid malfunction, open or short circuit in control circuit. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Four-wheel drive indicator flashing
  • Problems with switching transfer case modes
  • Deterioration in off-road handling
  • Clicking or other unusual sounds from the transfer case

Causes

  • Transfer case solenoid malfunction
  • Open or short circuit in control circuit
  • Poor contact in connectors
  • Mechanical valve jamming
  • Problems with the transfer box control unit

How to Fix

  1. Check the integrity of the wiring harness to the solenoid
  2. Check solenoid resistance (usually 10-30 ohms)
  3. Clean the connector contacts
  4. Check the mechanical operation of the valve
  5. Replace faulty solenoid if necessary
  6. Reset the error and check the system operation

Related codes

Error C0402 by Vehicle Brand

FAQ

What does the C0402 code mean?

C0402 is an OBD-II diagnostic trouble code that indicates: Transfer Case Solenoid Valve

What causes a C0402 error code?

The most common causes of C0402 include: Transfer case solenoid malfunction; Open or short circuit in control circuit; Poor contact in connectors; Mechanical valve jamming.

How do I fix a C0402 diagnostic trouble code?

To fix C0402: Check the integrity of the wiring harness to the solenoid. Check solenoid resistance (usually 10-30 ohms). Clean the connector contacts. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with C0402?

Limited driving only, diagnose soon

How much does it cost to fix C0402?

The estimated repair cost for C0402 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat