What does it mean?
B1965 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Power Liftgate Sensor Supply Circuit Low .
Symptoms
- Power liftgate completely disabled, only manual operation left
- Several liftgate sensor codes stored at the same time, all pointing at the same reference
- Gate stops randomly or refuses to start a cycle
- Warning chime repeats when the gate button is pressed
- Fault appears after rain or a car wash and may clear when everything dries out
Likely causes
- Sensor supply wire shorted to ground in the liftgate boot or along the roof channel
- One sensor failed internally and loading the shared reference line
- Water in a sensor or module connector creating a leakage path
- Crushed harness where the loom passes the hinge or the D pillar
- Corroded terminals lowering the supply through voltage drop rather than a dead short
- Overloaded or failing regulator inside the liftgate control module
- Poor module power feed or ground, which pulls the whole reference down
How to fix it
- Measure the sensor supply voltage at the module connector with the ignition on and compare it with the specified reference level
- Disconnect the liftgate sensors one at a time and watch the reference, if it recovers when one is removed that sensor is loading the circuit
- With all sensors and the module unplugged, check the supply wire for continuity to ground and localise any short by section
- Inspect the harness through the gate boot and around the hinge for crushing and chafe
- Check the module power and ground with voltage drop tests before suspecting its internal regulator
- Dry and clean every connector on the circuit and repair corroded terminals
- Repair the shorted wire or replace the faulty sensor, then clear the codes, run a full gate cycle and confirm the reference stays stable