Description
When ignition switch is turned ON, IGNITION 1 voltage is applied from AIR BAG fuse to DERM at IGNITION 1 input terminal Nos. A9 and A10 and from GAUGES fuse to DERM at REDUNDANT INDICATOR IGNITION 1 input terminal No. B2. DERM responds by flashing AIR BAG indicator 7 times then turning off while performing tests on SIR system.
When engine is being cranked, system voltage is applied from CRANK fuse to DERM at CRANK input terminal No. B10. DERM responds by grounding SIR Indicator output terminal No. B1 until system voltage is removed from CRANK input. This results in AIR BAG indicator being on steady during cranking. After cranking, DERM will flash AIR BAG indicator 6 times and perform test on SIR system.
Note. Test numbers refer to test numbers on diagnostic table. For circuit number identification, see WIRING DIAGRAMS .
- 1) AIR BAG indicator should flash 7 times after ignition switch is turned to ON.
- 2) AIR BAG indicator should remain on steady during cranking.
- 3) After cranking, AIR BAG indicator should flash 6 times then turn off.
- 4) This test checks for proper operation of Serial Data line. Test also will determine whether history diagnostic trouble codes are stored and, if so, identify them.
- 5) This test checks for DERM ability to communicate through the Serial Data line.
- 6) This test refers to appropriate DTC table for diagnosis of history DTCs set to memory in DERM.
- 7) When AIR BAG warning light flashes four times during BULB TEST, this indicates a malfunction in redundant lamp driver circuitry. These malfunctions are diagnosed by DTC 62 table.
- 8) Improper operation of AIR BAG indicator is indicated. This test differentiates an indicator stays ON condition from an indicator does not come ON condition.