What does it mean?
C1405 is a Chassis (ABS, traction control, steering) fault code. It indicates: Transfer Case Range Position Sensor Circuit High .
Symptoms
- Service four wheel drive message with a warning lamp
- Position value pinned at the top of its range no matter which range is selected
- Shift requests refused, or the transfer case shifts and then reports a fault
- Indicator lamps stay off or flash continuously
- Fault often appears after underbody work or after driving through deep water
Likely causes
- Open circuit in the range position sensor signal or ground wire, so the module reads full reference voltage
- Sensor connector unplugged, partly seated or with a terminal backed out
- Signal wire shorted to a nearby battery or ignition feed
- Internally open sensor track or a broken wiper contact
- Corrosion inside the connector creating an effectively open joint
- Broken sensor ground shared with other components under the vehicle
- Control module input fault (least likely)
How to fix it
- Read the position sensor voltage in live data; a reading stuck at reference points to an open circuit
- Check the connector is fully seated and inspect for backed-out or corroded terminals
- With the ignition on, backprobe the sensor ground and confirm it is close to chassis potential
- Test the signal wire for continuity to the module pin and for a short to a voltage feed
- Bridge the signal to ground at the sensor connector and watch whether the reading falls, which proves the harness and module
- Inspect the underbody harness for breaks, pulled terminals and water damage
- Repair the open circuit or replace the position sensor, then confirm a complete range shift