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Home >> Cadillac >> 2017 >> XTS Base >> Repair and Diagnosis >> Body & Frame >> Seats >> Power Seat System >> Diagnostic Information and Procedures >> Power Seat Malfunction (With Seat Bolster Memory Control Module) >> Circuit/System Testing
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Circuit/System Testing

  1. Ignition OFF, disconnect the X2 harness connector at the appropriate K40 Seat Memory Control Module.
  2. Test for less than 10 Ω between ground circuit terminal 5 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. 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. Ignition OFF, disconnect the X1 harness connector at the K40 Seat Memory Control Module, ignition ON.
  4. Verify that a test lamp illuminates between the B+ circuit terminal 2 and ground.
    • If the test lamp does not illuminate. 
    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 circuit breaker is OK and there is voltage at the circuit breaker.
    • If the test lamp illuminates. 
  5. Ignition OFF, connect the X1 harness connector at the K40 Seat Memory Control Module and disconnect the harness connector at the appropriate seat motor listed below:
    • M50 Seat Front Vertical Motor
    • M55 Seat Rear Vertical Motor
    • M51 Seat Horizontal Motor
    • M56 Seat Recline Motor
  6. Connect a test lamp between control circuit terminal 1 and control circuit terminal 5, ignition ON.
    7. NOTE:

    Once a seat motor is commanded On using the scan tool, the seat function may not work using the seat adjuster switch until you back out of the scan tool Control Functions menu.

  7. Verify the test lamp turns ON when commanding the seat motor in the Up/Down or Forward/Rearward states with a scan tool.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF, disconnect the X3 harness connector at the K40 Seat Memory Control Module.
    2. Test for infinite resistance between each control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in each control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K40 Seat Memory Control Module.
    • If the test lamp turns ON during each of the commands 
  8. Test or replace the seat motor.
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