GM Service Manual Online
For 1990-2009 cars only

The SIR scan tool data definitions contain a brief description of all SIR related parameters available on the scan tool. The list is in the order the list appears on the scan tool.

Ignition: The scan tool displays the battery voltage. The ignition represents the system voltage that is measured by the SDM between terminal 5 and terminal 7.

Driver Frontal Resist.: The scan tool displays 0-6.6 ohms. The SDM performs the resistance measurement test once each ignition cycle and verifies the Ignition 1 and the 23 VLR voltages are within the normal ranges. Then the SDM sources a constant current to the driver deployment loop. The SDM then measures the voltage drop across the deployment loop and converts the measured voltage value to a driver deployment loop resistance value.

Pass. Frontal Resist.: The scan tool displays 0-6.6 ohms. The SDM performs the resistance measurement test once each ignition cycle and verifies the Ignition 1 and 23 VLR voltages are within the normal ranges. Then the SDM sources a constant current to the passenger deployment loop. The SDM then measures the voltage drop across the deployment loop and converts the measured voltage value to a passenger deployment loop resistance value.

LH Side Air Bag Resist.: The scan tool displays 0-6.6 ohms. The SDM performs the resistance measurement test once each ignition cycle and verifies the Ignition 1 and 23 VLR voltages are within the normal ranges. Then the SDM sources a constant current to the LH side air bag deployment loop. The SDM then measures the voltage drop across the deployment loop and converts the measured voltage value to a LH side air bag deployment loop resistance value.

RH Side Air Bag Resist.: The scan tool displays 0-6.6 ohms. The SDM performs the resistance measurement test once each ignition cycle and verifies the Ignition 1 and 23 VLR voltages are within the normal ranges. Then the SDM sources a constant current to the RH side air bag deployment loop. The SDM then measures the voltage drop across the deployment loop and converts the measured voltage value to a RH side air bag deployment loop resistance value.

LH Pretens. Resist.: The scan tool displays 0-6.6 ohms. The SDM performs the resistance measurement test once each ignition cycle and verifies the Ignition 1 and 23 VLR voltages are within the normal ranges. Then the SDM sources a constant current to the driver seat belt pretensioner deployment loop. The SDM then measures the voltage drop across the deployment loop and converts the measured voltage value to a driver seat belt pretensioner deployment loop resistance value.

RH Pretens. Resist.: The scan tool displays 0-6.6 ohms. The SDM performs the resistance measurement test once each ignition cycle and verifies the Ignition 1 and 23 VLR voltages are within the normal ranges. Then the SDM sources a constant current to the passenger seat belt pretensioner deployment loop. The SDM then measures the voltage drop across the deployment loop and converts the measured voltage value to a passenger seat belt pretensioner deployment loop resistance value.

Driver Frontal Senselo: The scan tool displays 0-20 volts. The SDM measures the voltage at the driver frontal low terminal 2 and displays this value as Driver Frontal Senselo.

Passenger Frontal Senselo: The scan tool displays 0-20 volts. The SDM measures the voltage at the passenger frontal low terminal 3 and displays this valus as Passenger Frontal Senselo.

LH Side Air Bag Senselo: The scan tool displays 0-20 volts. The SDM measures the voltage at the LH side air bag low terminal 10 and displays this value as LH Side Air Bag Senselo.

RH Side Air Bag Senselo: The scan tool displays 0-20 volts. The SDM measures the voltage at the RH side air bag low terminal 14 and displays this value as RH Side Air Bag Senselo.

LH Pretens. Senselo: The scan tool displays 0-20 volts. The SDM measures the voltage at the driver seat belt pretensioner low terminal 9 and displays this value as LH Pretens. Senselo.

RH Pretens. Senselo: The scan tool displays 0-20 volts. The SDM measures the voltage at the passenger seat belt pretensioner low terminal 15 and displays this value as RH Pretens. Senselo.

Driver Frontal VDIF: The scan tool displays 0-500 millivolts. The SDM measures the voltage difference between driver frontal high and driver frontal low and displays this voltage difference as Driver VDIF.

Passenger VDIF: The scan tool displays 0-500 millivolts. The SDM measures the voltage difference between passenger frontal high and passenger frontal low and displays this voltage difference as Passenger VDIF.

LH Side Air Bag VDIF: The scan tool displays 0-500 millivolts. The SDM measures the voltage difference between driver side high and driver side low and displays this voltage difference as LH Side Air Bag VDIF.

RH Side Air Bag VDIF: The scan tool displays 0-500 millivolts. The SDM measures the voltage difference between passenger side high and passenger side low and displays this voltage difference as RH Side Air Bag VDIF.

LH Pretensioner VDIF: The scan tool displays 0-500 millivolts. The SDM measures the voltage difference between driver belt high and driver belt low and displays this voltage difference as LH Pretensioner VDIF.

RH Pretensioner VDIF: The scan tool displays 0-500 millivolts. The SDM measures the voltage difference between passenger belt high and passenger belt low and displays this voltage difference as RH Pretensioner VDIF.

Warning Lamp ON: The scan tool displays 0-182 hours. The SDM measures the continuous warning lamp ON time.

Warning Lamp Cycles: The scan tool displays 0-125 cycles. The ignition cycles of the current warning lamp state.

Driver Seat Belt: The scan tool displays Buckled or Unbuckled. The SDM determines this by looking at whether the driver seat belt is buckled or unbuckled.