P1866
Transmission Transfer Case System Concern Servicing Required
Severity
⚠️ MediumCan you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–89 (est.)
Symptoms
- Check Engine Light Is On
- Problems with switching all-wheel drive modes
- Unusual noises from the transfer case
- Reduced all-wheel drive efficiency
Causes
- Low oil level in transfer case
- Problems with solenoid valves
- Wear of mechanical components
- Errors in the operation of the electronic control module
- Wiring damage
How to Fix
- Check the level and condition of the oil in the transfer case
- Diagnose transfer case solenoid valves
- Check the condition of mechanical components
- Scan the electronic control module for errors
- Inspect the integrity of the wiring and contacts