What does it mean?
B1420 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Side-airbag module (RH) (squib) system fault 1 (short circuit between terminals of the squib circuit) .
Symptoms
- Airbag warning lamp on from the first ignition cycle after the fault occurs
- Right side airbag disabled and will not fire in a side impact
- Fault often shows up right after seat removal, seat cover fitting or valeting
- Code returns immediately as current after any attempt to clear it
- Nothing else changes in the way the vehicle drives
Likely causes
- Harness under the seat crushed by the seat rails or by objects pushed under the seat
- Yellow connector under the seat partly unlatched, so its shorting bar keeps both squib pins bridged
- Insulation damaged during seat removal, seat cover fitting or upholstery repair
- Moisture or spilled liquid soaked into the seat base reaching the connector
- Internal short inside the side airbag module built into the seat backrest
- Non original seat covers or a wrong airbag module fitted with an out of range initiator
- Faulty measuring circuit in the restraint control module
How to fix it
- Switch off the ignition, disconnect the battery and wait the specified reserve energy discharge time before going under the seat
- Find the yellow connector under the seat and check that it is fully latched, undamaged and free of moisture and debris
- Look for harness sections crushed by the seat rails or trapped by items stored under the seat
- Reseat the connector, clear the code and see whether the fault stays away, since a partly mated connector is a very common cause
- Substitute the manufacturer approved load tool or simulator for the airbag module to decide whether the fault is in the harness or in the module
- Repair damaged harness sections properly, or renew the section rather than taping over it
- Replace the side airbag module with the correct part number if the simulator proves the wiring good, then clear the codes and confirm the lamp goes out