What Does B2231 Mean?
This code indicates the airbag control module (ACM) has detected a short to battery voltage in the passenger airbag circuit loop #2. The module monitors continuity and resistance in the airbag squib circuits, and this fault means an unintended voltage source (typically 12V+) is present on the passenger airbag deployment circuit. This condition prevents proper airbag deployment and typically illuminates the airbag warning light on the instrument cluster.
Safety Warning
Not safe to drive as the passenger airbag is disabled and will not deploy in a collision, placing occupants at severe risk of injury. The vehicle should be repaired immediately before carrying passengers, as the SRS system is a critical safety device.
Common Causes
45%
Damaged or chafed wiring harness under passenger seat creating short to power wire
30%
Faulty passenger airbag clockspring or damaged connectors at airbag module
15%
Water intrusion or corrosion in passenger airbag connector causing cross-circuit short
10%
Defective airbag control module with internal short circuit
Diagnostic Steps
1
Step 1: Perform visual inspection of passenger airbag wiring harness under seat, checking for pinched, chafed, or damaged wires near seat rails and mounting brackets. Look for signs of previous repair work or aftermarket seat modifications.
2
Step 2: Disconnect passenger airbag module connector and inspect for corrosion, bent pins, or moisture. Using a digital multimeter, measure resistance between airbag circuit pins at harness side (should read 2-3 ohms typically) and check for continuity to battery voltage (should read open/infinite resistance).
3
Step 3: With airbag connector still disconnected, measure voltage at airbag harness connector pins to ground with ignition ON. Should read 0V; any battery voltage present confirms short to power in harness between ACM and airbag.
4
Step 4: If short to battery is confirmed, isolate fault location by disconnecting ACM connector and re-testing circuit. If voltage disappears, ACM is faulty. If voltage remains, trace and repair harness short between ACM and passenger airbag.
5
Step 5: After repairs, clear codes, perform airbag system self-test using diagnostic tool, and verify proper resistance values across all airbag circuits before reconnecting components. Confirm warning light extinguishes and no codes return.
Estimated Repair Cost
$200 - $1,200
Parts + labor, varies by vehicle and location
This code indicates the airbag control module (ACM) has detected a short to battery voltage in the passenger airbag circuit loop #2. The module monitors continuity and resistance in the airbag squib circuits, and this fault means an unintended voltage source (typically 12V+) is present on the passen...
The most common cause of B2231 (Air Bag Passenger Circuit Short to Battery - Loop #2) is: Damaged or chafed wiring harness under passenger seat creating short to power wire
Typical repair costs for B2231 range from $200 to $1,200, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Not safe to drive as the passenger airbag is disabled and will not deploy in a collision, placing occupants at severe risk of injury. The vehicle should be repaired immediately before carrying passengers, as the SRS system is a critical safety device.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B2231 to identify the root cause.
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Quick Info
Category
Body
System
Supplemental Restraint System (SRS/Airbag)
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
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