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Circuit/System Testing

B3920 01 or B3920 02

  1. Ignition OFF, disconnect the X3 harness connector at the appropriate seat memory control module listed below:
    • K40D Seat Memory Control Module - Driver
    • K40P Seat Memory Control Module - Passenger
  2. Test for infinite resistance between each control circuit terminal listed below and ground:
    • Seat front vertical motor up control terminal 3
    • Seat front vertical motor down control terminal 4
    • Seat rear vertical motor up control terminal 5
    • Seat rear vertical motor down control terminal 6
    • Seat horizontal motor forward control terminal 11
    • Seat horizontal motor rearward control terminal 12
    • Seat recline motor forward control terminal 1
    • Seat recline motor rearward control terminal 2
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  3. Ignition ON.
  4. Test for less than 1 V between each control circuit terminal listed below and ground:
    • Seat front vertical motor up control terminal 3
    • Seat front vertical motor down control terminal 4
    • Seat rear vertical motor up control terminal 5
    • Seat rear vertical motor down control terminal 6
    • Seat horizontal motor forward control terminal 11
    • Seat horizontal motor rearward control terminal 12
    • Seat recline motor forward control terminal 1
    • Seat recline motor rearward control terminal 2
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • Go to next step: If less than 1 V 
  5. Replace the K40 Seat Memory Control Module.

B3920 00 or B3920 0B

  1. Ignition ON.
  2. Clear the current and history DTC.
  3. Determine which motor set this DTC by operating each seat motor listed below one at a time in both directions. Check for the DTC to set between each motor test.
    • M50 Seat Front Vertical Motor
    • M55 Seat Rear Vertical Motor
    • M51 Seat Horizontal Motor
    • M56 Seat Recline Motor
  4. Ignition OFF, disconnect the harness connector at the seat motor for which the DTC set, ignition ON.
  5. Clear the DTC.
  6. Verify that DTC B3920 00 or B3920 0B does not set while operating the seat motor adjuster switch in both directions.
    • If DTC B3920 00 or B3920 0B sets 
    1. Ignition OFF.
    2. Test for infinite resistance between control circuit terminal 1 and control circuit terminal 3.
      • If less than infinite resistance, repair the short between the circuits.
      • Go to next step: 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.
    • Go to next step: If DTC B3920 00 or B3920 0B does not set 
  7. Test or replace the seat motor.
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