For 1990-2009 cars

The scan tool used provides the following capabilities:

• | Read the data list.

• | Read current and history trouble codes.

• | Clear the diagnostic trouble codes after a repair is completed.

Make sure the scan tool contains an updated cartridge before attempting to communicate with the SIR system. To use the scan tool, connect it to the Data Link Connector (DLC) and turn the ignition switch to the ON position. The scan tool reads serial data sent from the inflatable restraint Sensing and Diagnostic Module (SDM) Serial Data output terminal 1 to the DLC terminal 9.

The SIR Scan Tool Data List contains all restraint related parameters that are available on the scan tool. The list is arranged in the order as they appear on the scan tool.

Use the SIR Scan Tool Data List only after the following is determined:

• | Diagnostic System Check is completed.

• | No Diagnostic Trouble Codes (DTCs) are set.

• | SIR Diagnostics indicates functioning properly.

Scan tool values from a properly operating system may be used for comparison with the SIR system you are diagnosing. The SIR Scan Tool Data List represents values seen on a properly operating system.

Important: Make sure the scan tool that you are using is functioning properly. Use of a malfunctioning scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis. If all values are within the typical range described below, refer to Intermittents and Poor Connections for diagnosis.

Scan Tool Parameter | Units Displayed | Typical Data Value
--- | --- | ---
Ignition ON, Engine OFF, and Driver Seat Belt Buckled
Ignition | Volts | 12 V
Lamp Driver | Internal/External | Internal
Driver Resistance | Ohms | 2.6 ohms
Passenger Resistance | Ohms | 2.2 ohms
Driver Senselo | Volts | 4.1 V
Passenger Senselo | Volts | 4.1 V
Driver VDIF | Millivolts | 4-8 mV
Passenger VDIF | Millivolts | 4-8 mV
Warning Lamp Control | On/Off | On
Lamp Driver Feedback | Active/Inactive | Inactive
Warning Lamp ON | Hours | 0-182 Hrs
Warning Lamp Cycles | Cycles | 0-125 Cycles
Driver Seat Belt | Buckled/Unbuckled | Buckled