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Circuit/System Testing

WARNING: This page is about a different car, the 2017 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the B109 Transfer Case Fluid Temperature Sensor.
    2. NOTE:
    • When test probing harness terminals, it is imperative to use the proper test probe from the most current version of the J 35616 GM-Approved Terminal Test Kit. Use of an improper test probe may deform the terminal, resulting in intermittent open conditions.
    • The low side driver of the low reference circuit has a high resistance to chassis ground, greater than 800 Ω.
    • Testing for steps 3-4 is performed on the B109 transfer case fluid temperature sensor harness / K69 transfer case control module harness using the GY probe J 35616-2A.
    • The low side driver of the low reference circuit has a high resistance to chassis ground when not activated, greater than 15 K Ω.
    • Testing for steps 2-3 is performed within 15 seconds of using the key fob to unlock the doors. After 15 seconds the voltage on the 5 V reference circuit will drop to 0.0 V.
    • An alternate method to using the key fob to activate the 5 V reference circuit is to perform steps 2-3 with the engine running. But the engine running, a voltage on the 5 volt reference circuit should be a constant 4.875-5.125 V.
  2. Test for 4.875-5.125 V between the transfer case 5 V reference circuit terminal A, and ground.
    • If less than 4.875 V 
    1. Ignition OFF, disconnect the X1 harness connector at the K69 Transfer Case Control Module.
    2. Test for infinite resistance between the 5 V reference circuit, K69 Transfer Case Control Module X1 harness terminal 9, and body ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the 5 V reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω
    4. Test for infinite resistance between the 5 V reference circuit, terminal 9, and all other pins of the K69 Transfer Case Control Module X1 harness connector.
      • If less than infinite resistance, repair the shorted together condition in the affected circuits.
      • If infinite resistance, replace the K69 Transfer Case Control Module and perform the Transfer Case Clutch Identifier Configuration/Reset Function. Refer to Transfer Case Control Module Scan Tool Information .
    • If greater than 5.125 V 
    1. Ignition OFF, disconnect the X1 harness connector at the K69 Transfer Case Control Module.
    2. Test for infinite resistance between the 5 V reference circuit, terminal 9, and all other pins of the K69 Transfer Case Control Module X1 harness connector.
      • If less than infinite resistance, repair the shorted together condition in the affected circuits.
      • If infinite resistance, replace the K69 Transfer Case Control Module and perform the Transfer Case Clutch Identifier Configuration/Reset Function. Refer to Transfer Case Control Module Scan Tool Information .
    • If between 4.875-5.125 V 
  3. Test for 4.875-5.125 V between the transfer case 5 V reference circuit terminal A, and the low reference circuit terminal B.
    • If less than 4.875 V 
    1. Ignition OFF, disconnect the X1 harness connector at the K69 Transfer Case Control Module.
    2. Test for infinite resistance between the low reference circuit, K69 Transfer Case Control Module X1 harness terminal 1, and body ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω
    4. Test for infinite resistance between the low reference circuit, terminal 1, and all other pins of the K69 Transfer Case Control Module X1 harness connector.
      • If less than infinite resistance, repair the shorted together condition in the affected circuits.
      • If infinite resistance, replace the K69 Transfer Case Control Module and perform the Transfer Case Clutch Identifier Configuration/Reset Function. Refer to Transfer Case Control Module Scan Tool Information .
    • If greater than 5.125 V 
    1. Ignition OFF, disconnect the X1 harness connector at the K69 Transfer Case Control Module.
    2. Test for infinite resistance between the low reference circuit, terminal 1, and all other pins of the K69 Transfer Case Control Module X1 harness connector.
      • If less than infinite resistance, repair the shorted together condition in the affected circuits.
      • If infinite resistance, replace the K69 Transfer Case Control Module and perform the Transfer Case Clutch Identifier Configuration/Reset Function. Refer to Transfer Case Control Module Scan Tool Information .
    • If between 4.875-5.125 V 
  4. 5 V reference circuit, transfer case oil temperature sensor low reference circuit, and the transfer case control module OK.
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