Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1998 Oldsmobile Aurora V8-4.0L VIN CFACTORY OEM SERVICE PROCEDURE
Scan Tool Data Definitions
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 date 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 as Passenger 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 Driver VDIF.
Warning Lamp Control: The scan tool displays ON or OFF. The warning lamp state commanded by the SDM.
Lamp Driver Feedback: The scan tool displays Active or Inactive. The warning lamp state detected by the SDM.
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.
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 date 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 as Passenger 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 Driver VDIF.
Warning Lamp Control: The scan tool displays ON or OFF. The warning lamp state commanded by the SDM.
Lamp Driver Feedback: The scan tool displays Active or Inactive. The warning lamp state detected by the SDM.
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.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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