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Home >> Cadillac >> 2012 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (Supplemental Inflatable Restraint System) >> Diagnostic Tests >> DTC B0077, B0079, B0080: EFS Valid Identification Message Not Received/EFS Identification Error/EFS NOK Message >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 GMC C3500 HD, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. If SIR Diagnostic System Check has been performed, go to next step. If SIR Diagnostic System Check has not been performed, go to SIR DIAGNOSTIC SYSTEM CHECK .
  2. Using scan tool, request SIR DTC display. If DTC B0079 or B0080, is retrieved as a current DTC, go to step  12. If DTC B0079 or B0080 is not retrieved as a current DTC, go to next step.
  3. Turn ignition off. Disconnect EFS connector. See ELECTRONIC FRONTAL SENSOR (EFS)  under REMOVAL & INSTALLATION. If connector is damaged or corroded, go to next step. If connector is okay, go to step  5.
  4. If EFS side of connector is damaged, replace EFS. Go to step  13. If harness side of connector is damaged, replace connector. See WIRE REPAIR . Go to step  10.
  5. Disconnect SDM connector. See Figure. If SDM connector or SDM terminals show signs of corrosion, poor connections or other damage, go to next step. If SDM connector and terminals are okay, go to step  7.
  6. If SDM connector is damaged, replace SDM connector. See WIRE REPAIR . Go to step  13. If SDM terminals are damaged, go to step  11.
    NOTE: Use Digital Multimeter (J-39200) and Connector Test Adapter Kit (J-35616-A) or Flat Wire Probe Adapter Kit (J-42675) when performing electrical tests.
  7. Test EFS signal circuit for an open, short to ground or high resistance. If open, high resistance or short to ground is found and corrected, go to step  13. If open, high resistance or short to ground is not found, go to next step.
  8. Turn ignition on. Check EFS signal and ground circuits for a short to voltage. If short to voltage is found and corrected, go to step  13. If short to voltage is not found, go to next step.
  9. Replace EFS. See ELECTRONIC FRONTAL SENSOR (EFS)  under REMOVAL & INSTALLATION. Go to next step.
  10. Reconnect SIR components. Using scan tool, clear all SIR DTC's. Road test vehicle, then check for DTC's. If DTC's are retrieved, go to next step. If DTC's are not retrieved, system is normal.
  11. Replace SDM. See SENSING & DIAGNOSTIC MODULE (SDM)  under REMOVAL & INSTALLATION. Go to next step.
  12. Replace EFS. See ELECTRONIC FRONTAL SENSOR (EFS)  under REMOVAL & INSTALLATION. Go to next step.
  13. Using scan tool, clear all SIR DTC's. Road test vehicle, then check for DTC's. If DTC is retrieved, go to step  2. If DTC is not retrieved, system is normal.
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