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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.

  • M101 Seat Belt Retractor Motor Module
  • M101 Seat Belt Retractor Motor Module harness connector
  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the M101 Seat Belt Retractor Motor Module. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the low reference circuit terminal 1 and ground.
    • If 10 Ω or greater 
    1. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Verify a test lamp illuminates between the B+ circuit terminal 4 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the disconnected control module.
    • If the test lamp illuminates 
  4. Ignition ON, verify a test lamp illuminates between each ignition circuit terminal and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ignition circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is OK and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    2. Test for infinite resistance between the ignition circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the disconnected control module.
    • If the test lamp illuminates 
  5. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.
  6. Test for less than 2 Ω in each of the serial data circuits end to end between the control module harness connector and the DLC terminals High speed GMLAN serial data circuit terminal 6 and 14
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 2 Ω 
  7. Replace the appropriate M101 Seat Belt Retractor Motor Module.
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