Passenger Airbag Circuit Short (B1935)
The B1935 code indicates that the Restraint Control Module (RCM) has detected a resistance below the minimum threshold (typically less than 1.3–2.0 ohms) in the passenger airbag inflator (squib) circuit. This suggests a short to ground, a short between the high and low circuit wires, or an internal failure of the RCM. The system will disable the passenger airbag and illuminate the airbag warning light.
1. Commonly Affected Makes
2. Most Common Causes
- Short to ground in the passenger airbag inflator circuit wiring (high or low side)
- Short circuit between the high and low wires of the inflator circuit
- Internal short in the passenger airbag inflator (squib) coil
- Damaged, corroded, or pushed-back terminals in connector C300 (under seat) or the RCM connector
- Faulty Sensing and Diagnostic Module (SDM/RCM)
3. Symptoms You Will Notice
- Airbag warning light illuminated on the dashboard
- Passenger airbag deactivated (may show 'Passenger Airbag Off' indicator)
4. Step-by-Step Diagnosis
Scan for codes and verify B1935 is present
Visually inspect connector C300 under the passenger seat and the RCM connector for damage, corrosion, or pushed pins
Measure resistance between the passenger airbag inflator circuit wires at the RCM connector; compare to specifications
If resistance is below threshold, disconnect the passenger airbag module and measure resistance at the module; if still low, replace the airbag module
If resistance is normal at the module, check for a short in the wiring harness between the RCM and the airbag module
If all wiring and components test good, replace the RCM
5. Frequently Asked Questions
Is it safe to drive?▼
The vehicle can be driven, but the passenger airbag will be disabled, increasing injury risk in a crash. Have the system repaired as soon as possible.
How much does it cost to fix?▼
Diagnosis typically costs $100–$150. Repair costs vary: wiring repair $150–$300, airbag module replacement $300–$800, RCM replacement $500–$1,200 (including labor).