What does it mean?
B1272 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Sliding Door Optical Sensor-2 Output Stuck High .
Symptoms
- The power sliding door refuses to operate under power or stops part way through its travel
- The door reverses with no obstruction present
- A warning chime or message appears when the door button is pressed
- The fault may only appear after the door has been cycled several times
- Manual operation of the door still works
Likely causes
- Open circuit in the optical sensor signal or supply wire, leaving the module input high
- Sensor connector disconnected or a terminal backed out inside the sliding door
- Broken conductor in the flexible harness at the sliding door hinge or track
- Internal failure of the second optical sensor unit
- Corrosion in the sensor connector from water running down inside the door
- Signal wire shorted to battery voltage
How to fix it
- Check the second optical sensor status in live data while interrupting its beam by hand
- Inspect and reseat the sensor connector inside the door and look for corrosion
- Flex the harness at the door hinge while watching live data, since a changing value confirms a broken conductor
- Measure the sensor supply voltage, ground, and signal continuity back to the sliding door module
- Repair the broken harness with correctly rated flexible wire, or replace the sensor if it never responds
- Clear the code and cycle the door fully several times to confirm the repair