What does it mean?
B1524 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Buckle Switch Passenger Open or Short to Ground .
Symptoms
- Airbag warning lamp on
- Passenger belt chime and lamp behave as if the belt is never fastened, or never activate at all
- Belt state in scan data frozen regardless of the buckle
- Fault appears or clears as the passenger seat is moved
- Passenger belt pretensioner logic disabled
Likely causes
- Under-seat connector unplugged or partly seated, a common result of cleaning or removing the passenger seat
- Broken conductor inside the harness at the point where it flexes with seat travel
- Buckle cable chafed through onto the seat frame, grounding the signal permanently
- Contaminated switch contacts after a drink was spilled into the buckle
- Corroded terminal that has lost contact, or one that has backed out and touches the seat structure
- Worn out buckle switch that no longer closes reliably
- Wiring pinched under a seat mounting bolt during reassembly
How to fix it
- Watch the passenger buckle state in live data while latching and releasing several times
- Check the buckle mouth for coins, food debris, dried liquid and any latch bypass insert
- Unplug and reseat the under-seat connector, inspecting for corrosion, pushed-out terminals and moisture
- With the buckle unplugged, measure switch resistance in both positions, then check the harness for continuity to ground
- Move the seat through its full travel while flexing the harness and watching for signal dropout
- Repair the broken or grounded section with proper terminals and secure it clear of the rails
- Replace the passenger buckle assembly if the switch tests faulty, then clear the code and confirm the repair