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Circuit/System Testing

NOTE:

Use the schematic to determine which devices are on the K9 Body Control Module's serial data communication enable circuit terminal 23 X4. Use the connector end view to identify the serial data communication enable circuit terminal for each of those devices.

  1. Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. Disconnect the harness connectors at the K9 Body Control Module. It may take up to 10 min for all vehicle systems to power down.
  2. Test for greater than 100 Ω between the serial data communication enable circuit terminal 23 X4 and ground.
    • If 100 Ω or less 
    1. Disconnect the harness connectors at all devices that share the serial data communication enable circuit.
    2. Test for infinite resistance between the serial data communication enable circuit terminal and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Reconnect the first device that shares the share the serial data communication enable circuit.
    4. Test for greater than 100 Ω between the serial data communication enable circuit terminal and ground.
      • If 100 Ω or less, replace the device that was just connected.
      • If greater than 100 Ω and there are more devices to connect, connect the next device and repeat step 2.4 until there are no more devices to connect.
    • Go to next step: If greater than 100 Ω 
  3. Replace the K9 Body Control Module.