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Circuit/System Testing

    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. 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 @ 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
    • Go to next step: If the specified state 
  7. Momentarily connect a 3 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 @ 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 less than 2 ohms between the test points: Signal circuit terminal 3 @ Component harness & Signal circuit terminal 7 @ M74D Window Motor - Driver
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: M74D Window Motor - Driver
    • Go to next step: 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 @ 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
    • Go to next step: 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 @ 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 less than 2 ohms between the test points: Signal circuit terminal 6 @ Component harness & Signal circuit terminal 3 @ M74D Window Motor - Driver
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: M74D Window Motor - Driver
    • Go to next step: If the specified state 
  10. Test for greater than 10 V between the test points: Signal circuit terminal 2 @ Component harness & Ground
    • If 10 V or less 
    1. Disconnect the electrical connector: M74D Window Motor - Driver
    2. Test for infinite resistance between the test points: Signal 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
    3. Test for less than 2 ohms between the test points: Signal circuit terminal 2 @ Component harness & Terminal 5 @ M74D Window Motor - Driver
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: M74D Window Motor - Driver
    • Go to next step: If greater than 10 V 
  11. Test or replace the component: S79D Window Switch - Driver
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