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Circuit/System Testing

Test 1

    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.

  1. Ignition/Vehicle & All vehicle systems » Off
  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 MotorGround circuit terminal 1 at 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 MotorB+ circuit terminal 2 at 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

Test 2

    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.

  1. Ignition/Vehicle & All vehicle systems » Off
  2. Disconnect the electrical connector: S79D Window Switch - Driver
  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: Ground circuit terminal 1 at 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 4 & Ground
    • If the test lamp does not turn On and the circuit fuse is OK 
    1. Ignition/Vehicle » Off & Remove » Test lamp
      • 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 4 & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance » Replace the component: S79D Window Switch - Driver
    • If the test lamp turns On 
  6. Verify the scan tool parameter: Driver Window Main Control Down Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74D Window Motor - Driver
    3. Test for infinite resistance between the test points: Signal circuit terminal 3 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance » Replace the component: M74D Window Motor - Driver
    • If the specified state 
  7. Momentarily connect a 7 A fused jumper wire between the test points: Signal circuit terminal 3 & Ground circuit terminal 1

    Verify the scan tool parameter: Driver Window Main Control Down Switch = Active

    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74D Window Motor - Driver
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 3 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 3 at Component harness & Terminal 7 at M74D Window Motor - DriverComponent harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74D Window Motor - Driver
    • If the specified state 
  8. Verify the scan tool parameter: Driver Window Main Control Up Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74D Window Motor - Driver
    3. Test for infinite resistance between the test points: Signal circuit terminal 6 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance » Replace the component: M74D Window Motor - Driver
    • If the specified state 
  9. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 6 & Ground circuit terminal 1

    Verify the scan tool parameter: Driver Window Main Control Up Switch = Active

    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74D Window Motor - Driver
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 6 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 6 at Component harness & Terminal 3 at M74D Window Motor - DriverComponent harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74D Window Motor - Driver
    • If the specified state 
  10. Verify the scan tool parameter: Driver Window Main Control Express Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74D Window Motor - Driver
    3. Test for infinite resistance between the test points: Signal circuit terminal 2 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance » Replace the component: M74D Window Motor - Driver
    • If the specified state 
  11. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 2 & Ground circuit terminal 1

    Verify the scan tool parameter: Driver Window Main Control Express Switch = Active

    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74D Window Motor - Driver
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 2 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 2 at Component harness & Terminal 5 at M74D Window Motor - Driver Component harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74D Window Motor - Driver
    • If the specified state 
  12. Test or replace the component: S79D Window Switch - Driver

Test 3

    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.

  1. Ignition/Vehicle & All vehicle systems » Off
  2. Disconnect the electrical connector: X1S79P Window Switch - Passenger
  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 10 Ω between the test points: Ground circuit terminal 1 at 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 the scan tool parameter: Passenger Window Switch at Door = Inactive
    • If not the specified state 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74P Window Motor - Passenger
    3. Test for infinite resistance between the test points:
      • Signal circuit terminal 7 at Component harness & Ground
      • Signal circuit terminal 8 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance » Replace the component: M74P Window Motor - Passenger
    • If the specified state 
  6. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 8 at Component harness & Ground
  7. Verify the scan tool parameter: Passenger Window Switch at Door = Up
    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74P Window Motor - Passenger
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 8 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 8 at Component harness & Terminal 8 at M74P Window Motor - Passenger Component harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74P Window Motor - Passenger
    • If the specified state 
  8. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 7 at Component harness & Ground
  9. Verify the scan tool parameter: Passenger Window Switch at Door = Down
    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74P Window Motor - Passenger
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 7 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 7 at Component harness & Terminal 7 at M74P Window Motor - PassengerComponent harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74P Window Motor - Passenger
    • If the specified state 
  10. Test for greater than 10 V between the test points: Signal circuit terminal 6 at Component harness & Ground
    • If 10 V or less 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74P Window Motor - Passenger
    3. Test for infinite resistance between the test points: Signal circuit terminal 6 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If less than infinite resistance
    1. Test for less than 2 Ω between the test points: Signal circuit terminal 6 at Component harness & Terminal 5 at M74P Window Motor - PassengerComponent harness
    • If the specified state 
  11. Test or replace the component: S79P Window Switch - Passenger

Test 4

    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.

  1. Ignition/Vehicle & All vehicle systems » Off
  2. Disconnect the electrical connector: S79LR Window Switch - Left Rear
  3. Test for less than 2 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: Ground circuit terminal 1 at 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 the scan tool parameter: Left Rear Window Switch at Door = Inactive
    • If not the specified state 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74LR Window Motor - Left Rear
    3. Test for infinite resistance between the test points:
      • Signal circuit terminal 6 at Component harness & Ground
      • Signal circuit terminal 7 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance » Replace the component: M74LR Window Motor - Left Rear
    • If the specified state 
  6. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 6 at Component harness & Ground
  7. Verify the scan tool parameter: Left Rear Window Switch at Door = Up
    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74LR Window Motor - Left Rear
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 6 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 3 at Component harness & Terminal 6 at M74LR Window Motor - Left Rear Component harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74LR Window Motor - Left Rear
    • If the specified state 
  8. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 7 at Component harness & Ground
  9. Verify the scan tool parameter: Left Rear Window Switch at Door = Down
    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74LR Window Motor - Left Rear
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 6 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 6 at Component harness & Terminal 3 at M74LR Window Motor - Left Rear Component harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74LR Window Motor - Left Rear
    • If the specified state 
  10. Test for greater than 10 V between the test points: Signal circuit terminal 8 at Component harness & Ground
    • If 10 V or less 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74LR Window Motor - Left Rear
    3. Test for infinite resistance between the test points: Signal circuit terminal 8 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If less than infinite resistance
    1. Test for less than 2 Ω between the test points: Signal circuit terminal 8 at Component harness & Terminal 5 at M74LR Window Motor - Left Rear Component harness
    • If the specified state 
  11. Test or replace the component: S79LR Window Switch - Left Rear

Test 5

    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.

  1. Ignition/Vehicle & All vehicle systems » Off
  2. Disconnect the electrical connector: S79RR Window Switch - 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: Ground circuit terminal 1 at Component harness & Ground 10Connection
      • 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 the scan tool parameter: Right Rear Window Switch at Door = Inactive
    • If not the specified state 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74RR Window Motor - Right Rear
    3. Test for infinite resistance between the test points:
      • Signal circuit terminal 6 at Component harness & Ground
      • Signal circuit terminal 7 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance » Replace the component: M74RR Window Motor - Right Rear
    • If the specified state 
  6. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 6 at Component harness & Ground
  7. Verify the scan tool parameter: Right Rear Window Switch at Door = Up
    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74RR Window Motor - Right Rear
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 6 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 6 at Component harness & Terminal 3 at M74RR Window Motor - Right Rear Component harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74RR Window Motor - Right Rear
    • If the specified state 
  8. Momentarily connect a 3 A fused jumper wire between the test points: Signal circuit terminal 6 at Component harness & Ground
  9. Verify the scan tool parameter: Right Rear Window Switch at Door = Down
    • If not the specified state 
    1. Ignition/Vehicle » Off & Remove » Jumper wire(s)
    2. Disconnect the electrical connector: M74RR Window Motor - Right Rear
    3. Ignition » On / Vehicle » In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 6 at Component harness & Ground
      • If 1 V or greater » Repair the short to voltage on the circuit.
      • If less than 1 V
    5. Ignition/Vehicle » Off
    6. Test for less than 2 Ω between the test points: Signal circuit terminal 6 at Component harness & Terminal 3 at M74RR Window Motor - Right Rear Component harness
      • If 2 Ω or greater » Repair the open/high resistance in the circuit.
      • If less than 2 Ω » Replace the component: M74RR Window Motor - Right Rear
    • If the specified state 
  10. Test for greater than 10 V between the test points: Signal circuit terminal 8 at Component harness & Ground
    • If 10 V or less 
    1. Ignition/Vehicle » Off
    2. Disconnect the electrical connector: M74RR Window Motor - Right Rear
    3. Test for infinite resistance between the test points: Signal circuit terminal 8 at Component harness & Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If less than infinite resistance
    1. Test for less than 2 Ω between the test points: Signal circuit terminal 8 at Component harness & Terminal 5 at M74RR Window Motor - Right Rear Component harness
    • If the specified state 
  11. Test or replace the component: S79RR Window Switch - Right Rear
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