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 it appears on the scan tool.
Ignition: The scan tool displays 0-25.5 volts. The Ignition
represents the system voltage measured by the SDM at its ignition feed.
Lamp Driver: The scan tool displays Internal or External. The warning lamp control
method for a hard wired lamp is Internal. The warning lamp control method
for a serial data controlled lamp is External.
Driver Resistance: The scan tool displays 0-6.3 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.
Passenger Resistance: The scan tool displays 0-6.3 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.
Driver Senselo: The scan tool displays 0-20 volts. The SDM measures
the voltage of the driver low terminal voltage and displays it as Driver Senselo.
Passenger Senselo: The scan tool displays 0-20 volts. The SDM measures
the voltage of the passenger low terminal voltage and displays it as Passenger
Senselo.
Driver VDIF: The scan tool displays 0-500 millivolts. The SDM measures
the voltage difference between driver high and driver low and displays this
voltage difference asDriver VDIF.
Passenger VDIF: The scan tool displays 0-500 millivolts. The SDM measures
the voltage difference between passenger high and driver low and displays
this voltage difference as Passenger 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 signal from the
drivers seat belt switch that the seat belt is fastened.