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Circuit/System Testing

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF and all vehicle systems OFF, disconnect the KR149A Folding Top Pump Motor Relay 1 and KR149B Folding Top Pump Motor Relay 2. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuits listed below and ground:
    • K149A Folding Top Pump Motor Relay 1 - Ground circuit terminal 5
    • K149A Folding Top Pump Motor Relay 1 - Ground circuit terminal 6
    • K149B Folding Top Pump Motor Relay 2 - Ground circuit terminal 5
    • K149B Folding Top Pump Motor Relay 2 - Ground circuit terminal 6
    • 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.
    • Go to next step: If less than 10 Ω 
  3. Verify a test lamp illuminates between the B+ circuits listed below and ground.
    • K149A Folding Top Pump Motor Relay 1 - B+ circuit terminal 2
    • K149B Folding Top Pump Motor Relay 2 - B+ circuit terminal 2
    • 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, remove the test lamp, disconnect the harness connector at the K23 Folding top Control Module.
    2. Test for infinite resistance between the circuits listed and ground.
      • K149A Folding Top Pump Motor Relay 1 - B+ circuit terminal 2
      • K149B Folding Top Pump Motor Relay 2 - B+ circuit terminal 2
      • K149A Folding Top Pump Motor Relay 1 - Control circuit terminal 8
      • K149B Folding Top Pump Motor Relay 2 - Control circuit terminal 8
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K23 Folding Top Control Module.
    • Go to next step: If the test lamp illuminates 
  4. Connect a test lamp between the control circuit terminals listed below and ground, ignition ON.
    • K149A Folding Top Pump Motor Relay 1 - Control circuit terminal 4
    • K149B Folding Top Pump Motor Relay 2 - Control circuit terminal 4
  5. Verify the test lamp turns ON and OFF when commanding the appropriate KR149 Folding Top Pump Motor Relay On and Off with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K23 Folding Top Control Module.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the 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 K23 Folding Top Control Module.
    • If the test lamp is always ON 
    1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K23 Folding Top Control Module, ignition ON.
    2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K23 Folding Top Control Module.
    • Go to next step: If the test lamp turns ON and OFF 
  6. Ignition OFF, disconnect the K23 Folding Top Control Module.
  7. Test for less than 2 Ω in the signal circuits listed below.
    • K149A Folding Top Pump Motor Relay 1 - Control circuit terminal 8 and K23 Folding Top Control Module - Signal circuit terminal 22 X6
    • K149B Folding Top Pump Motor Relay 2 - Control circuit terminal 8 and K23 Folding Top Control Module - Signal circuit terminal 23 X6
    • If greater than 2 Ω 

      Repair the open/high resistance in the circuit.

    • Go to next step: If 2 Ω or less 
  8. Connect the KR149A Folding Top Pump Motor Relay 1 and KR149B Folding Top Pump Motor Relay 2.
  9. Ignition ON, connect a test lamp between the M23 Folding Top Pump Motor control circuit terminal 1 and M23 Folding Top Pump Motor control circuit terminal 2.
  10. Verify that a test lamp turns ON and OFF when commanding the KR149A Folding Top Pump Motor Relay 1 and KR149B Folding Top Pump Motor Relay 2 On and Off with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, remove the test lamp, disconnect the KR149A Folding Top Pump Motor Relay 1 and KR149B Folding Top Pump Motor Relay 2.
    2. Test for less than 2 Ω in the control circuits end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, test or replace appropriate KR149A Folding Top Pump Motor Relay 1 or KR149B Folding Top Pump Motor Relay 2.
    • If the test lamp is always ON 
    1. Ignition OFF, remove the test lamp, disconnect the KR149A Folding Top Pump Motor Relay 1 and KR149B Folding Top Pump Motor Relay 2.
    2. Test for less than 1 V between the control circuits and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, test or replace the appropriate KR149A Folding Top Pump Motor Relay 1 or KR149B Folding Top Pump Motor Relay 2.
    • Go to next step: If the test lamp turns ON and OFF 
  11. Replace the M23 Folding Top Pump Motor.
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