What does it mean?
B2231 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Passenger-side Air Bag Module (Inflator No.2) Circuit Short To Power Supply .
Symptoms
- Air bag warning lamp on and the passenger restraint deactivated.
- The passenger air bag second stage cannot fire in a severe frontal impact.
- The passenger air bag status indicator behaves inconsistently.
- The fault appears after dash, audio or glove box work, or after a water leak into the cabin.
- The code is stored as current and returns immediately after clearing.
Likely causes
- Chafed dash harness under the passenger side where the squib wire rubs against a powered circuit or a bracket.
- Water intrusion from the windshield seal or air conditioning drain into the passenger air bag connector, bridging pins.
- Trim screw, glove box fastener or accessory bracket driven through the loom during previous work.
- Aftermarket wiring for a camera, alarm or entertainment system spliced into the dash harness near the restraint circuits.
- Bent, corroded or pushed back terminal in the passenger air bag connector.
- Internal fault in the passenger air bag module shorting the second squib to a powered path.
- Restraint control module output stage failure on that loop.
How to fix it
- Disconnect the battery and observe the specified stand down time before unplugging any restraint connector.
- Read all restraint codes to establish whether one loop or several circuits are affected.
- Unplug the passenger air bag module and check whether the code changes to an open circuit fault, which would place the short inside the module.
- With the module disconnected, measure the harness side squib wires for battery voltage with the key both on and off.
- Inspect the passenger foot well and under dash loom for water staining, chafe marks, screws through the harness and non factory splices.
- Repair the harness with sealed crimped joints and reroute it clear of brackets and sharp edges, and cure any water leak.
- Replace the air bag module only once the wiring is proven clean, then clear the codes and confirm a normal lamp self test.