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Circuit/System Testing

Speaker Circuit Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate P19 speaker. Ignition On/Vehicle in Service Mode. Infotainment system ON, mute OFF.
  2. Test for 5-7 V between the appropriate signal circuit terminals listed below and ground.
    • Door and Left I/P, Right I/P, Rear shelf, Rear center speakers audio (-) circuit terminal 1
    • Door and Left I/P, Right I/P, Rear shelf, Rear center speakers audio (+) circuit terminal 2
    • A-Pillar speakers audio (-) circuit terminal 3
    • A-Pillar speakers audio (+) circuit terminal 4
    • Center I/P speakers audio (-) circuit terminal 6
    • Center I/P speakers audio (+) circuit terminal 1
    • Headrest speakers audio (-) circuit terminal A
    • Headrest speakers audio (+) circuit terminal B
    • If less than 5 V 
    1. Ignition OFF, disconnect the appropriate harness connector(s) at the T3 audio amplifier.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the T3 audio amplifier.
    • If greater than 7 V 
    1. Ignition OFF, disconnect the appropriate harness connector(s) at the T3 audio amplifier.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the T3 audio amplifier.
    • If between 5-7 V 
  3. Test or replace the P19 speaker.

Subwoofer Circuit Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the appropriate secondary audio amplifier.
  2. Test for less than 10 Ω between the appropriate ground circuit terminal listed below and ground.
    • Left and Right Front Subwoofer circuit terminal 6
    • Rear Subwoofer circuit terminal 14
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • 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 
  3. Ignition On/Vehicle in Service Mode. Verify a test lamp illuminates between the appropriate B+ circuit terminal listed below and ground.
    • Left and Right Front Amplifier circuit terminal 3
    • Rear Amplifier circuit terminal 7
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF, remove the test lamp.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF, remove the test lamp.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the secondary amplifier
    • If the test lamp illuminates 
  4. Ignition OFF, disconnect the X1 harness connector at the appropriate secondary amplifier, Ignition On/Vehicle in Service Mode.
  5. Radio ON, Test for 2.5-3.5 V between the appropriate control circuit listed below and ground.
    • Left and Right Front Amplifier circuit terminal 2
    • Rear Amplifier circuit terminal 5
    • If less than 2.5 V 
    1. Ignition OFF, disconnect the appropriate harness connector at the T3 Audio Amplifier.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the T3 Audio Amplifier.
    • If greater than 3.5 V 
    1. Ignition OFF, disconnect the appropriate harness connector at the T3 Audio Amplifier.
    2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the T3 Audio Amplifier.
    • If between 2.5-3.5 V 
  6. Radio ON, mute OFF.
  7. Test for 3-5 V between the appropriate signal circuit terminals listed below and ground:
    • Left and Right front subwoofer control (+) circuit terminal 4
    • Left and Right front subwoofer control (-) circuit terminal 5
    • Rear Subwoofer control (+) circuit terminal 3
    • Rear Subwoofer control (-) circuit terminal 2
    • If less than 3 V 
    1. Ignition OFF, disconnect the X4 harness connector at the T3 Amplifier.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the T3 audio amplifier.
    • If greater than 5 V 
    1. Ignition OFF, disconnect the X4 harness connector at the T3 amplifier, Ignition On/Vehicle in Service Mode.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the T3 audio amplifier.
    • If between 3-5 V 
  8. Ignition OFF, connect all harness connectors.
  9. Disconnect the harness connector at the appropriate P19 Speaker. Ignition On/Vehicle in Service Mode. Radio ON.
  10. Test for 5-7 V between the appropriate signal circuit terminals listed below and ground:
    • Left and Right front subwoofer control (+) circuit terminal 2
    • Left and Right front subwoofer control (-) circuit terminal 1
    • Rear Subwoofer control (+) circuit terminal B
    • Rear Subwoofer control (-) circuit terminal A
    • If less than 5 V 
    1. Ignition OFF, disconnect the X1 harness connector at the Secondary Amplifier.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the secondary amplifier.
    • If greater than 7 V 
    1. Ignition OFF, disconnect the X1 harness connector at the Secondary amplifier, Ignition On/Vehicle in Service Mode.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the Secondary amplifier.
    • If between 5-7 V 
  11. Test or replace the P19 Speaker.
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