What does it mean?
B1537 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Seat belt switch (RH) circuit open (for common terminal) .
Symptoms
- Airbag warning lamp on
- Right belt reminder completely unresponsive: no chime and no change of indication
- No valid belt state reported for the right seat in scan data
- Several right belt switch codes stored at the same time, because both contacts lose their return
- Fault typically appears straight after seat removal or interior work
Likely causes
- Under-seat connector unplugged or partly seated, breaking the shared return leg
- Broken conductor in the common wire where the loom flexes with seat travel
- Corroded or spread terminal on the common pin, giving high resistance
- Buckle pigtail broken at the point where it leaves the buckle body
- Internal break inside the buckle at the shared return path
- Harness cut or poorly repaired during earlier seat, carpet or trim work
How to fix it
- Check how many right belt switch codes are stored; a group of them points to the shared common leg
- Unplug and reseat the under-seat connector, inspecting the common terminal for corrosion and spreading
- Measure continuity of the common wire from the buckle connector to the module connector
- Flex the loom through the full seat travel while watching continuity for a break that comes and goes
- Inspect the pigtail at the buckle body for a conductor broken under the insulation
- Repair the open with proper crimped terminals instead of a twisted joint
- Replace the right buckle assembly if the break is internal, then clear the code and confirm the belt state changes