What does it mean?
B1433 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Side-airbag module (LH) (squib) system fault power supply circuit (short-circuited to power supply) .
Symptoms
- Airbag warning lamp on permanently and the left side airbag disabled
- Fault often follows seat heater repair, seat replacement or accessory fitting
- Code is current at every ignition cycle and returns instantly after being cleared
- Seat heating, seat position memory or occupant detection codes may set alongside it
- Engine, brakes and general driveability remain completely normal
Likely causes
- Squib harness rubbed through against a seat heater, seat motor or lumbar supply wire in the same loom
- Accessory wiring spliced into the driver seat harness during a previous installation
- Corrosion or spilled liquid in the under seat connector bridging the squib pin to a live pin
- Loom crushed between the seat frame and a powered bracket or a floor mounted accessory
- Internal fault in the left side airbag module connecting the initiator to its supply side
- Badly made repair joint where circuits were bundled together without proper insulation
- Restraint control module output stage feeding voltage into the initiator circuit
How to fix it
- Turn the ignition off, disconnect the battery and observe the specified reserve energy discharge time
- Unplug the left side airbag module and inspect the connector for corrosion, moisture and pins forced across to a supply terminal
- Follow the driver seat loom and separate the initiator pair from any live wires taped in with them
- Remove or correctly reroute any aftermarket wiring that has been spliced into the seat harness
- With the module unplugged, check the squib wires for supply voltage with the ignition switched on
- Repair the damaged insulation or replace the harness section, routing the squib pair away from powered circuits
- Fit a new side airbag module only after the harness has been proven clean, then clear the memory and confirm the lamp extinguishes