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Home >> Cadillac >> 2008 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 141 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> DTC B1287 >> Circuit/System Testing
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Circuit/System Testing

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  1. Ignition OFF, disconnect the X3 harness connector at the audio amplifier.
  2. Ignition ON, radio ON and un-muted, test for 0.5-1.0 volts between the amplifier control circuit terminal 11 and ground.
    • If greater than the specified value, test the amplifier control circuit for a short to voltage. If the circuit tests normal, replace the radio.
    • If less than the specified value, test the amplifier control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
  3. If all circuits test normal, replace the amplifier.