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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: P19B Speaker - Center Instrument Panel
  3. Test for less than 10 ohms between the test points: Ground circuit terminal 10 @ Component harness & Ground
    • If 10 ohms or greater 
    1. Disconnect the ground connection: G202
    2. Test for less than 2 ohms between the test points: Ground circuit terminal 10 @ Component harness & Ground
      • 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. Verify a test lamp turns On between the test points: B+ circuit terminal 5 & Ground
    • If the test lamp does not turn On and the circuit fuse is OK 
    1. Remove - Test Lamp
    2. Test for less than 2 ohms between the test points: B+ circuit terminal 5 & F30DA Fuse
      • 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. Remove - Test Lamp
    2. Test for infinite resistance between the test points: B+ circuit terminal 5 & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component: P19B Speaker- Center Instrument Panel.
    • Go to next step: If the test lamp turns On 
  5. Ignition/Vehicle - Off & Remove - Test lamp
  6. Disconnect the electrical connector: T3 Audio Amplifier
  7. Ignition On/Vehicle in Service Mode.
  8. Test for less than 1 V between the test points:
    • Signal circuit terminal 3 @ Component harness & Ground
    • Signal circuit terminal 4 @ Component harness & Ground
    • Signal circuit terminal 7 @ Component harness & Ground
    • Signal circuit terminal 8 @ Component harness & Ground
    • Signal circuit terminal 9 @ 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
    1. Test for infinite resistance between the test points:
      • Signal circuit terminal 3 & Ground
      • Signal circuit terminal 4 & Ground
      • Signal circuit terminal 7 & Ground
      • Signal circuit terminal 8 & Ground
      • Signal circuit terminal 9 & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    2. Test for less than 2 ohms between the test points:
      • Signal circuit terminal 3 @ Component harness & Terminal 13 @ Control module harness
      • Signal circuit terminal 4 @ Component harness & Terminal 12 @ Control module harness
      • Signal circuit terminal 7 @ Component harness & Terminal 11 @ Control module harness
      • Signal circuit terminal 8 @ Component harness & Terminal 15 @ Control module harness
      • Signal circuit terminal 9 @ Component harness & Terminal 14 @ Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • Go to next step: If less than 2 ohmsReplace the component: P19B Speaker - Center Instrument Panel
  9. Ignition - On / Vehicle - In Service Mode Radio = On
  10. Verify the center speakers raise from dashboard.
    • If speakers do not raise from dashboard

      Replace the component: T3 Audio Amplifier

    • Go to next step: If speakers do raise from dashboard
  11. All OK.
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