What Does B1929 Mean?
This code indicates the airbag control module has detected an open circuit in the safing sensor output circuit. The safing sensor is a critical safety redundancy component that must confirm crash forces before allowing airbag deployment. An open circuit means the module cannot receive signal from this sensor, preventing proper airbag system operation and disabling the supplemental restraint system.
Safety Warning
The vehicle is unsafe to drive as the airbag system is disabled and will not deploy in a crash, significantly increasing injury risk. This requires immediate professional diagnosis and repair before operating the vehicle.
Common Causes
45%
Damaged or corroded wiring harness connector at safing sensor or control module
30%
Failed safing sensor with internal open circuit
20%
Broken or severed wire in safing sensor circuit between sensor and control module
5%
Faulty airbag control module with internal circuit failure
Diagnostic Steps
1
Step 1: Perform visual inspection of safing sensor location (typically mounted near or on airbag control module) and check connector for corrosion, damage, pushed-out pins, or moisture intrusion. Ensure connector is fully seated and locked.
2
Step 2: Using a digital multimeter, backprobe the safing sensor connector and measure resistance across sensor terminals (typically 2-10 ohms for most sensors). Compare to manufacturer specifications. An infinite reading confirms internal sensor failure.
3
Step 3: Disconnect safing sensor connector and measure continuity of circuit wiring from sensor connector pins to airbag control module connector pins. Should read less than 5 ohms resistance. Infinite reading indicates open wire that must be traced and repaired.
4
Step 4: Inspect airbag control module mounting location for evidence of water intrusion, physical damage, or collision damage. Check control module connector terminals for corrosion or damage using magnification.
5
Step 5: If all wiring and connectors test good, replace safing sensor and clear codes. Road test vehicle and verify code does not return and airbag warning light remains off.
6
Step 6: If code persists after sensor replacement with confirmed good wiring, replace airbag control module and perform system reinitialization per manufacturer procedure.
Estimated Repair Cost
$200 - $1,200
Parts + labor, varies by vehicle and location
This code indicates the airbag control module has detected an open circuit in the safing sensor output circuit. The safing sensor is a critical safety redundancy component that must confirm crash forces before allowing airbag deployment. An open circuit means the module cannot receive signal from th...
The most common cause of B1929 (Air Bag Safing Sensor Output Circuit Open) is: Damaged or corroded wiring harness connector at safing sensor or control module
Typical repair costs for B1929 range from $200 to $1,200, depending on the vehicle, location, and whether you do it yourself or go to a shop.
The vehicle is unsafe to drive as the airbag system is disabled and will not deploy in a crash, significantly increasing injury risk. This requires immediate professional diagnosis and repair before operating the vehicle.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1929 to identify the root cause.
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Quick Info
Category
Body
System
Supplemental Restraint System (Airbag System)
Difficulty
Type
Manufacturer
Recommended Tools
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