Nubira SX Hatchback L4-2.0L DOHC D-TEC MFI (1999)
Malfunction Lamp / Indicator: Description and Operation
The Instrument Cluster contains an AIRBAG warning indicator. To verify the operation of the AIRBAG indicator and the sensing and diagnostic module
(SDM), the SDM performs a turn-on test when the ignition is turned ON. The SDM flashes the AIRBAG indicator seven times by supplying an
intermittent ground to the indicator lamp circuit. After flashing seven times, the AIRBAG indicator will turn off if no malfunctions have been detected.
The AIRBAG indicator stays on if the SDM has detected malfunctions in the internal or external circuits which could potentially affect the operation of
the supplemental inflatable restraint (SIR) system. Some malfunctions could result in non-deployment when necessary or deployment under conditions
which would not normally result in deployment.
When the SDM is not properly attached to its connector, the AIRBAG circuit is shorted to ground because there is a shorting bar within the SDM
electrical connector. The shorting bar is disengaged when a proper connection is made, but if a poor connection exists the SDM connector supplies a
ground to the AIRBAG indicator independently of the SDM, and the AIRBAG indicator turns on.
