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HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 7 (SUPPLEMENTAL INFLATABLE RESTRAINT SYSTEM)DIAGNOSTIC CHARTSSIR DIAGNOSTIC SYSTEM CHECKDESCRIPTION
1999 GMC Forward Control 5.7 R, Automatic

Sir Diagnostic System Check: Description

1999 GMC Forward Control 5.7 R, AutomaticSECTION Description
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 1996 GMC Vandura Special, 1996 GMC Vandura, 1996 GMC Savana Special, 1996 GMC Savana Camper Special, and 1996 GMC Savana. However, it is still accessible from the selected car via links, so may be relevant.

Ignition switch supplies IGNITION 1 voltage to inflatable restraint control module at terminal No. 10 using AIR BAGS fuse. When ignition switch is first turned to RUN, inflatable restraint control module responds by flashing AIR BAG warning light 7 times then turning off while performing tests on SIR system.

NOTE: Test numbers refer to test numbers on diagnostic table. For circuit number identification, see WIRING DIAGRAMS  .
  1. AIR BAG warning light should flash 7 times after ignition switch is turned to RUN.
  2. Improper operation of AIR BAG warning light is indicated. This test differentiates an warning light stays ON condition from an warning light does not come ON condition.
  3. The AIR BAG warning light should turn off after flashing 7 times.
  4. This test checks for proper operation of Serial Data line.
  5. This test will identify stored diagnostic trouble codes and whether they are current or history.
  6. This test checks for proper operation of Serial Data Line. This test also identifies any stored history diagnostic trouble codes.
RENDER: 1.0x

NO RELATED

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