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Home >> Cadillac >> 2017 >> CT6 Plug-In >> Repair and Diagnosis >> Body & Frame >> Fixed And MOVEABLE Windows >> Diagnostic Information and Procedures >> Power Windows Malfunction >> Circuit/System Testing >> Test 1
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Test 1

  1. Ignition/Vehicle & All vehicle systems» Off
    NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.
  2. Disconnect the appropriate electrical connector:
    • M74D Window Motor - Driver
    • M74P Window Motor - Passenger
    • M74LR Window Motor - Left Rear
    • M74RR Window Motor - Right Rear
  3. Test for less than 10 Ω between the test points: Ground circuit terminal 1 & Ground
    • If 10 Ω or greater 
    1. Ground Connection» Disconnect
    2. Test for less than 2 Ω between the test points: M74 Window Motor Ground circuit terminal 1 @ Component harness & Ground Connection
      • 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 
  4. Ignition» On / Vehicle» In Service Mode
  5. Verify a test lamp turns On between the test points: B+ circuit terminal 2 & Ground
    • If the test lamp does not turn On and the circuit fuse is OK 
    1. Ignition/Vehicle» Off & Remove» Test lamp
    2. Test for less than 2 Ω between the test points: M74 Window Motor B+ circuit terminal 2 @ Output terminal & Fuse
      • If 2 Ω or greater» Repair the open/high resistance in the circuit.
      • If less than 2 Ω» Verify the fuse is OK and there is voltage at the fuse.
    • If the test lamp does not turn On and the circuit fuse is open 
    1. Ignition/Vehicle» Off & Remove» Test lamp
    2. Test for infinite resistance between the test points: B+ circuit terminal 2 & Ground
      • If less than infinite resistance» Repair the short to ground on the circuit.
      • If infinite resistance» Replace the component: M74 Window Motor
    • If the test lamp turns On 
  6. Test or replace the component: M74 Window Motor