Case Study: Chevy Silverado airbag warning light on

Vehicle: 2005 Chevy Silverado 2500, 4WD, V8-6.6L DSL Turbo, VIN 2

Mileage: 175,776

Problem: This Silverado arrived in the shop with the supplemental restraints system (SRS) warning light illuminated.

Case Details: The technician connected a scan tool and retrieved the following diagnostic trouble codes (DTCs):

• B0024 - Driver Frontal Deployment Loop Voltage Out of Range
• B0026 - Driver Frontal Deployment Loop Open

The technician replaced the driver's airbag clockspring and cleared the DTCs. When he re-scanned for DTCs, the Inflatable restraint sensing and diagnostics module (SDM) would not communicate with the scan tool. A quick call to ALLDATA Tech-Assist resulted in some helpful advice. The Tech-Assist consultant told the technician that the SDM communicates on a single-wire Class 2 Serial Data network and recommended verifying the integrity of the Class 2 circuit between the SDM and the diagnostic link connector (DLC). He also mentioned since the SDM is located beneath the driver's seat, its connectors can get corroded or broken and the wires can get pinched or damaged by personal items stuffed under the seat. He also recommended checking the wiring and connectors at the clockspring since there was communication before the clockspring was replaced. After finding no problems with the wiring at or between the SDM and DLC, the technician rechecked the clockspring wiring. He found a loose connection.

Confirmed Repair: The technician crimped the connections to achieve a tighter pin fit. Communication with the SDM was restored. The technician cleared the DTCs and test drove the vehicle. No DTCs returned. Problem solved!

Reprinted with permission from ALLDATA.