C0550

What it means

The transfer case control module has detected a circuit fault on the encoder position switch — the contact pack reporting which range the encoder motor has reached. A fault disables 4WD shifting until the switch or wiring is repaired.

Is it safe to drive?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

• Encoder position switch contacts worn

  high

  One of the most commonly reported causes for this code — check this first.

• Wiring or connector fault

  medium

  A plausible cause — test and verify before replacing parts.

• Internal control module fault

  low

  Less common, but worth ruling out after the more likely causes.

Related help

• Full C0550 diagnosis, causes & costs
• How to read check engine light codes
• Is it safe to drive with the light on?