The following diagnostic procedure must be used when all circuitry outside the sensing and diagnostic module (SDM) has been found to operate properly, as indicated by following the appropriate DTC table. The procedure verifies the need for SDM replacement.
Circuit Description
When the SDM recognizes ignition voltage greater than 9 volts at the SDM, the air bag indicator flashes 7 times to verify operation. At this time the SDM performs turn-on tests followed by resistance measurement tests and continuous monitoring tests.
When malfunction is detected, the SDM sets a current DTC and illuminates the air bag indicator.
When the malfunction is no longer detected and/or the ignition switch is cycled, the SDM will clear current DTCs and move them to a history file, except for the DTCs 032, 033, 034, 035, 038, B1620, B1650, B1670 and sometimes 071. DTCs 032, 033, 034, 035, 038, B1620, B1650, B1670 will not be cleared by a scan tool because these codes require replacement of the SDM. The SDM must be replaced only after the malfunction that set the DTC has been repaired.
Step | Action | Yes | No |
|---|---|---|---|
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Caution: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Caution in the Preface section. Caution: Refer to Sensing and Diagnostic Module Handling Caution in the Preface section. Schematic Reference: SIR Schematics Connector End View Reference: SIR Connector End Views | |||
1 |
Does the indicator lamp flash 7 times? | Go to Step 2 | |
2 |
Is the same DTC displayed that occurred when the Diagnostic System Check - Vehicle was previously performed? | Go to Step 3 | |
3 |
Does the indicator lamp flash 7 times? | System OK | Go to Step 4 |
4 |
Did you complete the action? | -- | |
