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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 electrical connector: S79D Window Switch - Driver
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 1 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 1 @ Component harness & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  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 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - 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
    • Go to next step: If the test lamp turns On 
  6. Connect the electrical connector.S79D Window Switch - Driver
  7. Disconnect the electrical connector: M74D Window Motor - Driver
  8. Connect a test lamp between the test points: Signal circuit terminal 3 & B+
  9. Ignition - On / Vehicle - In Service Mode
  10. Operate the component: S79D Window Switch - Driver - Pulled

    Verify the test lamp state:

    S79D Window Switch - Driver - Not Used = Test lamp Off

    S79D Window Switch - Driver - Pulled = Test lamp On

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: S79D Window Switch - Driver
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 3 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points: Signal circuit terminal 3 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points: Signal circuit terminal 3 @ Component harness & Signal circuit terminal 6 @ S79D Window Switch - Driver
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: S79D Window Switch - Driver
    • Go to next step: If the specified state 
  11. Connect a test lamp between the test points: Signal circuit terminal 7 & B+
  12. Ignition - On / Vehicle - In Service Mode
  13. Operate the component: S79D Window Switch - Driver - Pressed

    Verify the test lamp state:

    S79D Window Switch - Driver - Not Used = Test lamp Off

    S79D Window Switch - Driver - Pressed = Test lamp On

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: S79D Window Switch - Driver
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 7 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points: Signal circuit terminal 7 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points: Signal circuit terminal 7 @ Component harness & Signal circuit terminal 3 @ S79D Window Switch - Driver
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: S79D Window Switch - Driver
    • Go to next step: If the specified state 
  14. Connect a test lamp between the test points: Signal circuit terminal 5 & B+
  15. Ignition - On / Vehicle - In Service Mode
  16. Operate the component: S79D Window Switch - Driver - Pressed & Pulled

    Verify the test lamp state:

    S79D Window Switch - Driver - Not Used = Test lamp Off

    S79D Window Switch - Driver - Pressed = Test lamp On

    S79D Window Switch - Driver - Pulled = Test lamp On

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: S79D Window Switch - Driver
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Signal circuit terminal 5 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points: Signal circuit terminal 5 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points: Signal circuit terminal 5 @ Component harness & Signal circuit terminal 2 @ S79D Window Switch - Driver
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: S79D Window Switch - Driver
    • Go to next step: If the specified state 
  17. Test or replace the component: M74D Window Motor - Driver

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: S79P Window Switch - Passenger
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 1 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 1@ Component harness & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  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 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - 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: S79P Window Switch - Passenger
    • Go to next step: If the test lamp turns On 
  6. Ignition/Vehicle - Off
  7. Connect the electrical connector.S79P Window Switch - Passenger
  8. Disconnect the electrical connector: M74P Window Motor - Passenger
  9. Connect a test lamp between the test points: Control circuit terminal 1 & Control circuit terminal 2
  10. Ignition - On / Vehicle - In Service Mode
  11. Perform the scan tool control function: Passenger Window Motor

    Verify the test lamp state:

    Passenger Window Motor - Stop = Test lamp Off

    Passenger Window Motor - Up = Test lamp On

    Passenger Window Motor - Down = Test lamp On

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: S79P Window Switch - Passenger
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:
      • Control circuit terminal 1 @ Component harness & Ground
      • Control circuit terminal 2 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points:
      • Control circuit terminal 1 @ Component harness & Ground
      • Control circuit terminal 2 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points:
      • Control circuit terminal 1 @ Component harness & Control circuit terminal 3 @ S79P Window Switch - Passenger
      • Control circuit terminal 2 @ Component harness & Control circuit terminal 2 @ S79P Window Switch - Passenger
        • If 2 ohms or greater - Repair the open/high resistance in the circuit.
        • If less than 2 ohms - Replace the component: S79P Window Switch - Passenger
    • Go to next step: If the specified state 
  12. Test or replace the component: M74P Window Motor - Passenger

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: S79LR Window Switch - Left Rear
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 5 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 5 @ Component harness & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  4. Ignition - On / Vehicle - In Service Mode
  5. Verify a test lamp turns On between the test points: B+ circuit terminal 8 & Ground
    • If the test lamp does not turn On and the circuit fuse is OK 
    1. Ignition/Vehicle - Off & Remove - Test lamp
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - 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 8 & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component: S79LR Window Switch - Left Rear
    • Go to next step: If the test lamp turns On 
  6. Ignition/Vehicle - Off
  7. Connect the electrical connector.S79LR Window Switch - Left Rear
  8. Disconnect the electrical connector: M74LR Window Motor - Left Rear
  9. Connect a test lamp between the test points: Control circuit terminal 1 & Control circuit terminal 2
  10. Ignition - On / Vehicle - In Service Mode
  11. Perform the scan tool control function: Left Rear Window Motor

    Verify the test lamp state:

    Left Rear Window Motor - Stop = Test lamp Off

    Left Rear Window Motor - Up = Test lamp On

    Left Rear Window Motor - Down = Test lamp On

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: S79LR Window Switch - Left Rear
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:
      • Control circuit terminal 1 @ Component harness & Ground
      • Control circuit terminal 2 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points:
      • Control circuit terminal 1 @ Component harness & Ground
      • Control circuit terminal 2 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points:
      • Control circuit terminal 1 @ Component harness & Control circuit terminal 7 @ S79LR Window Switch - Left Rear
      • Control circuit terminal 2 @ Component harness & Control circuit terminal 6 @ S79LR Window Switch - Left Rear
        • If 2 ohms or greater - Repair the open/high resistance in the circuit.
        • If less than 2 ohms - Replace the component: S79LR Window Switch - Left Rear
    • Go to next step: If the specified state 
  12. Test or replace the component: M74LR Window Motor - Left Rear

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: S79RR Window Switch - Right Rear
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 5 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 5 @ Component harness & Ground Connection
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  4. Ignition - On / Vehicle - In Service Mode
  5. Verify a test lamp turns On between the test points: B+ circuit terminal 8 & Ground
    • If the test lamp does not turn On and the circuit fuse is OK 
    1. Ignition/Vehicle - Off & Remove - Test lamp
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - 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 8 & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component: S79RR Window Switch - Right Rear
    • Go to next step: If the test lamp turns On 
  6. Ignition/Vehicle - Off
  7. Connect the electrical connector.S79RR Window Switch - Right Rear
  8. Disconnect the electrical connector: M74RR Window Motor - Right Rear
  9. Connect a test lamp between the test points: Control circuit terminal 1 & Control circuit terminal 2
  10. Ignition - On / Vehicle - In Service Mode
  11. Perform the scan tool control function: Right Rear Window Motor

    Verify the test lamp state:

    Right Rear Window Motor - Stop = Test lamp Off

    Right Rear Window Motor - Up = Test lamp On

    Right Rear Window Motor - Down = Test lamp On

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: S79RR Window Switch - Right Rear
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:
      • Control circuit terminal 1 @ Component harness & Ground
      • Control circuit terminal 2 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points:
      • Control circuit terminal 1 @ Component harness & Ground
      • Control circuit terminal 2 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points:
      • Control circuit terminal 1 @ Component harness & Control circuit terminal 7 @ S79RR Window Switch - Right Rear
      • Control circuit terminal 2 @ Component harness & Control circuit terminal 6 @ S79RR Window Switch - Right Rear
        • If 2 ohms or greater - Repair the open/high resistance in the circuit.
        • If less than 2 ohms - Replace the component: S79RR Window Switch - Right Rear
    • Go to next step: If the specified state 
  12. Test or replace the component: M74RR Window Motor - Right Rear
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