B0040 Possible Causes
- Faulty Driver's Side Air Bag Module
- Driver's Side Air Bag Module harness is open or shorted
- Driver's Side Air Bag Module circuit poor electrical connection
How do I fix code B0040
Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
Cost of diagnosing the B0040 code
Labor: 1.0The cost of diagnosing the B0040 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
B0040 Possible Symptoms
- Air Bag Warning Light ON
B0040 MeaningWhen ignition switch is turned to RUN position, Sensing and Diagnostic Module (SDM) performs tests to diagnose critical internal malfunctions. SDM then performs deployment loop voltage out of range test and deployment loop resistance measurement test. If voltage out of range test detects a short to voltage condition, resistance measurement test will not be performed.
B0040 More InformationNeed more information on how to fix the B0040 code?
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B0040 Information for specific makes
- B0040 BUICK Driver Side Deployment Loop Resistance Low
- B0040 CADILLAC Driver Side Deployment Loop Resistance Low
- B0040 CHEVROLET Driver Side Deployment Loop Resistance Low
- B0040 GMC Driver Side Deployment Loop Resistance Low
- B0040 PONTIAC Driver Side Deployment Loop Resistance Low
- B0040 SATURN Driver Side Deployment Loop Resistance Low
Precautions for SRS “AIR BAG” and “SEAT BELT PRE-TENSIONER” Service
- Never probe the electrical connectors on air bag, side air curtain modules or seat belts.
- Never disassemble or tamper with safety belt buckle/retractor pretensioners, adaptive load limiting retractors, safety belt inflators, or probe the electrical connectors.
- Do not use electrical test equipment to check SRS circuits unless instructed to in this Service Manual.
- Before servicing the SRS, turn ignition switch OFF, disconnect both battery cables and wait at least 3 minutes. For approximately 3 minutes after the cables are removed, it is still possible for the air bag and seat belt pre-tensioner to deploy. Therefore, do not work on any SRS connectors or wires until at least 3 minutes have passed.