Circuit/System Description
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
The inflatable restraint sensing and diagnostic module (SDM) stores a 4-digit primary key for the inflatable restraint vehicle roll over sensor (ROS). The SDM sends the ROS the primary key. If the ROS determines that it is the wrong primary key, the ROS will set DTC B1001 and send the SDM a vehicle mismatch message. The SDM then will set DTC B0090 3A and illuminate the SIR Warning Indicator. The ROS does not use a secondary key.