GM Service Manual Online
For 1990-2009 cars only

Important: Before rezeroing the passenger presence system (PPS), the front passenger seat must be completely empty of all items. The presence of any items on the front passenger seat will affect the calibration and operation of the PPS.

If the PPS is replaced or serviced, perform the rezeroing procedure for the PPS. Refer to Passenger Presence System Rezeroing for the rezeroing procedure.