When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform a turn-on test to diagnose critical malfunctions within the SDM itself.

Upon passing these tests, the ignition and deployment loop voltages are measured to ensure that these voltages are within the normal ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deployment loops.

The SDM tests the wiring connection to extra devices, such as the side impact sensor, by letting an infinitesimal current flow through the internal circuit to verify the resistance. If the voltage is out of range, the SDM is unable to test the airbag system properly.

In the case of DTC B1103 or B1104, test the battery and if necessary replace the battery with a new one.

Erase the DTC using the scan tool.

This diagnostic procedure supports the following DTC:

DTC B1104 Passenger Seat Occupant Classification System (OCS) Voltage Out of Range

Ignition voltage is within the normal operating voltage range.

The voltage supplied from the battery remains less than 10.6 volts for 16 seconds.

The SDM commands the AIR BAG indicator ON.

The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.