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Circuit/System Testing

NOTE:

When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

  • B153D Seat Belt Buckle-Driver
  • Seat belt switch harness connector
  • K36 Inflatable Restraint Sensing and Diagnostic Module
  • Inflatable Restraint Sensing and Diagnostic Module wiring harness connector
  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B153D Seat Belt Buckle-Driver. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 5 Ω between the low reference circuit terminal 2 and ground.
    • If 5 Ω or greater 
    1. Disconnect the X2 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.
    2. Test for less than 2 Ω in each low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
    • If less than 5 Ω 
  3. Ignition ON.
  4. Verify the scan tool Driver Seat Belt Status parameter is Buckled.
    • If not Buckled 
    1. Ignition OFF, disconnect the X2 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.
    2. Test for infinite resistance between the seat belt switch signal circuit terminal 1 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
    • If Buckled 
  5. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2.
  6. Verify the scan tool Driver Seat Belt Status parameter is Unbuckled.
    • If Unbuckled 
    1. Ignition OFF, disconnect the X2 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Test for less than 2 Ω in each circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
    • If Unbuckled 
  7. Test or replace the B153D Seat Belt Buckle-Driver.