What does it mean?
C1456 is a Chassis (ABS, traction control, steering) fault code. It indicates: AWD-Clutch-Power-Control-Circuit-LO .
Symptoms
- AWD or 4WD warning lamp and a system message, with the drive system disabled
- Little or no torque sent to the second axle, so the driven wheels spin easily
- Loss of traction on wet, snowy or loose surfaces
- Occasional shudder as the clutch drops out during a turn
- Stability and traction warnings appearing alongside this code
Likely causes
- Short to ground in the supply or control wire going to the AWD coupling clutch coil
- Chafed harness at the rear differential or coupling where it is exposed to stones and road spray
- Water and corrosion inside the coupling connector
- Internally shorted clutch coil with resistance below specification
- Poor ground or a partly blown fuse feeding the AWD control module
- Damaged output driver in the AWD control module
- Harness trapped or wrongly routed after previous underbody work
How to fix it
- Read AWD clutch current or duty cycle on live data while the system is commanded
- Inspect the underbody harness and the coupling connector for chafing, water and corrosion
- Measure the clutch coil resistance and compare it with specification; a low value points to an internal short
- With the coil unplugged, check the control wire for a short to ground
- Command the clutch with a scan tool and watch the current response
- Verify module power, ground and fuse condition
- Repair the harness or replace the coupling or coil; replace the control module last