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Home >> Cadillac >> 2019 >> CTS Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 123 (Cellular System, Entertainment System, And Navigation System - Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> Speaker Malfunction (IOS/IOT) >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page is about a different car, the 2018 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the appropriate P19 Speaker. Ignition ON, infotainment system ON, mute OFF.
  2. Test for 5 - 7 V between each audio signal circuit terminal 1 and terminal 2 and ground.
    • If less than 5 V 
    1. Ignition OFF, disconnect the X1 and X2 harness connectors 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.
      • Go to next step: 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 X1 and X2 harness connectors at the T3 Audio Amplifier. Ignition ON.
    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.
    • Go to next step: If between 5 - 7 V 
  3. Test or replace the P19 Speaker.