What does it mean?
B1378 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Power Tailgate Right Pinch Sensor Circuit Malfunction .
Symptoms
- The power tailgate stops or reverses part way through its travel for no obvious reason
- Power close is disabled altogether and the tailgate has to be shut by hand
- Warning chime or a message about the power tailgate at each attempt
- The fault often appears only in wet weather or after the tailgate has been slammed
- Obstacle detection no longer protects the right side of the opening, which matters if children use the vehicle
Likely causes
- Pinch strip cut, crushed or pulled part way out of its channel on the right side of the opening
- Water in the pinch sensor connector at the lower right of the tailgate aperture
- Broken conductor in the flexible section of the strip harness that moves with the tailgate
- Strip aged and cracked so its internal resistance has drifted outside tolerance
- Terminal backed out or corroded after body repair or trim removal
- Strip trapped and damaged by a slammed tailgate or by loaded cargo
- Tailgate control module input fault
How to fix it
- Check whether the left strip is also reporting a fault, since one side only points at that strip and its wiring
- Inspect the full length of the right strip for cuts, crush marks and places where it has come out of its channel
- Measure the strip resistance at its connector and compare it with the left strip, which makes a good reference on the same vehicle
- Flex the harness at the hinge area while watching the reading for jumps and open circuits
- Dry and clean the connector, and trace any water path into it
- Replace the pinch strip when its resistance is out of range or unstable
- Re-initialise the power tailgate travel after the repair if the manufacturer requires it, then test obstacle detection with a soft object