What does it mean?
B1729 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Inflatable curtain airbag rear-Passenger resistance circuit short to Battery .
Symptoms
- Airbag warning lamp on and the rear passenger-side curtain deactivated
- No side curtain protection on that side in a rollover or side impact
- Fault present continuously and reappears at once after clearing
- Frequently traced to a recent accessory fit or bodywork
- Other circuits on the same connector may fail together with it
Likely causes
- Squib wire chafed against a permanently live conductor sharing the same roof or pillar route
- Non-factory wiring for lighting, alarm, camera or audio contacting the SRS loom
- Corrosion bridging the squib pin to a live pin inside the rear pillar connector
- Terminal pushed back after a connector repair and touching the adjacent contact
- Curtain inflator with an internally shorted element
- Harness damaged in a previous rear-quarter or tailgate repair
- Restraint control module driver stage failure
How to fix it
- Record all SRS codes and their status before touching anything
- Disconnect the battery and wait the specified stand-down period
- Separate the squib connector, fit an approved load tool and check whether the fault remains
- With the module connector released, test both squib wires for voltage and for continuity to a live circuit
- Inspect the roof-rail and pillar loom for rub-through and for any aftermarket wiring routed alongside it
- Remove or reroute the offending wiring and repair damaged insulation with SRS repair leads
- Replace the curtain inflator if the short is internal; the control module is the last suspect