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Home >> Cadillac >> 2007 >> CTS Base, 2.8 T, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 747 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> Speaker Malfunction >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page is about a different car, the 2013 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:

On Right Hand Drive (RHD) Models, only the Amplifier X3 connector is different from Left Hand Drive (LHD).

Amplifier Circuit Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the audio amplifier.
  2. Ignition OFF, test for less than 1 V between the ground circuit terminal 8 and ground.
    • If greater than the specified range, test the ground circuit for an short to voltage.
  3. Ignition OFF, test for less than 10 Ω between the ground circuit terminal 8 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, test for B+ between the B+ circuit terminal 4 and ground.
    • If less then specified value, test the circuit for a short to ground, or an open/high resistance.
  5. Ignition OFF, disconnect the X3 harness connector at the audio amplifier.
  6. For RPO UQA only: Radio ON, test for B+ between the Entertainment remote enable circuit terminal 8 and ground.
    • If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
  7. If all circuits test normal, replace the audio amplifier.

Speaker Malfunction Radio Output Testing RPO UQA - LHD

  1. Ignition OFF, disconnect the X3 connector at the amplifier.
  2. Radio ON, test for a varying mV AC voltage reading between the appropriate signal circuit terminals listed below and ground.
    • Left front low level audio signal (+) - terminal 15 X3
    • Left front low level audio signal (-) - terminal 7 X3
    • Right front low level audio signal (+) - terminal 14 X3
    • Right front low level audio signal (-) - terminal 6 X3
    • Left rear low level audio signal (+) - terminal 13 X3
    • Left rear low level audio signal (-) - terminal 5 X3
    • Right rear low level audio signal (+) - terminal 12 X3
    • Right rear low level audio signal (-) - terminal 4 X3
    • If the varrying Mv A/C voltage reading is not present, test the signal circuit for a short to voltage, 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.

Speaker Malfunction Radio Output Testing RPO UQA - RHD

  1. Ignition OFF, disconnect the X3 connector at the amplifier.
  2. Radio ON, test for a varying mV AC voltage reading between the appropriate signal circuit terminals listed below and ground.
    • Left front low level audio signal (+) - terminal 14 X3
    • Left front low level audio signal (-) - terminal 6 X3
    • Right front low level audio signal (+) - terminal 15 X3
    • Right front low level audio signal (-) - terminal 7 X3
    • Left rear low level audio signal (+) - terminal 12 X3
    • Left rear low level audio signal (-) - terminal 4 X3
    • Right rear low level audio signal (+) - terminal 13 X3
    • Right rear low level audio signal (-) - terminal 5 X3
    • If the varrying Mv A/C voltage reading is not present, test the signal circuit for a short to voltage, 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.

Speaker Malfunction Radio Output Testing RPO UQS

  1. Ignition OFF, disconnect the X3 and X4 harness connectors at the amplifier.
  2. Ignition ON, radio ON, test for a varying mV AC voltage reading between the appropriate signal circuit terminals listed below and ground.
    • Left front low level audio signal (+) - terminal 11 X3
    • Left front low level audio signal (-) - terminal 12 X3
    • Right front low level audio signal (+) - terminal 3 X3
    • Right front low level audio signal (-) - terminal 4 X3
    • Left rear low level audio signal (+) - terminal 11 X4
    • Left rear low level audio signal (-) - terminal 12 X4
    • Right rear low level audio signal (+) - terminal 3 X4
    • Right rear low level audio signal (-) - terminal 4 X4
    • Center channel low level audio signal (+) - terminal 13 X4
    • Center channel low level audio signal (-) - terminal 14 X4
    • Subwoofer low level audio signal (+) - terminal 5 X4
    • Subwoofer low level audio signal (-) - terminal 6 X4
    • If the varrying Mv A/C voltage reading is not present, test the signal circuit for a short to voltage, 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.

Speaker Malfunction Amplifier Output Testing RPO UQA

  1. Ignition OFF, disconnect the X1 and X2 connectors at the amplifier.
  2. Radio ON, test for less than 1 V between the appropriate signal circuit terminal listed below and ground:
    • Left front speaker output (+) - terminal 5 X1
    • Left front speaker output (-) - terminal 1 X1
    • Right front speaker output (+) - terminal 8 X2
    • Right front speaker output (-) - terminal 7 X2
    • Left rear speaker output (+) - terminal 15 X2
    • Left rear speaker output (-) - terminal 16 X2
    • Right rear speaker output (+) - terminal 2 X2
    • Right rear speaker output (-) - terminal 1 X2
    • Front center speaker output (+) - terminal 4 X2
    • Front center speaker output (-) - terminal 3 X2
    • Rear subwoofer speaker output (+) - terminal 7 X1
    • Rear subwoofer speaker output (-) - terminal 3 X1
    • If greater than the specified range, test both circuits of the affected speaker for a short to voltage.
  3. Radio ON, test for infinite resistance between the appropriate signal circuit terminal listed below and ground:
    • Left front speaker output (+) - terminal 5 X1
    • Left front speaker output (-) - terminal 1 X1
    • Right front speaker output (+) - terminal 8 X2
    • Right front speaker output (-) - terminal 7 X2
    • Left rear speaker output (+) - terminal 15 X2
    • Left rear speaker output (-) - terminal 16 X2
    • Right rear speaker output (+) - terminal 2 X2
    • Right rear speaker output (-) - terminal 1 X2
    • Front center speaker output (+) - terminal 4 X2
    • Front center speaker output (-) - terminal 3 X2
    • Rear subwoofer speaker output (+) - terminal 7 X1
    • Rear subwoofer speaker output (-) - terminal 3 X1
    • If less than the specified value, test both circuits of the affected speaker for a short to ground.
  4. If all circuits test normal, reconnect all harness connectors at the amplifier.
  5. Ignition ON, radio ON, disconnect the appropriate speaker.
  6. Test for 5.0-7.5 V between the signal circuit terminals and ground.
    • If less then the specified range, test the circuit for an open/high resistance. If the circuit tests normal, replace the amplifier.
    • If greater then the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the amplifier.
  7. If the circuit tests normal, replace the appropriate speaker.

Speaker Malfunction Amplifier Output Testing RPO Code UQS

  1. Ignition OFF, disconnect the X1 and X2 connectors at the amplifier.
  2. Radio ON, test for less than 1 V between the appropriate signal circuit terminal listed below and ground:
    • Left front tweeter speaker output (+) - terminal 4 X2
    • Left front tweeter speaker output (-) - terminal 5 X2
    • Right front tweeter speaker output (+) - terminal 7 X2
    • Right front tweeter speaker output (-) - terminal 6 X2
    • Left rear speaker output (+) - terminal 16 X2
    • Left rear speaker output (-) - terminal 8 X2
    • Right rear speaker output (+) - terminal 15 X2
    • Right rear speaker output (-) - terminal 14 X2
    • Front center speaker output (+) - terminal 13 X2
    • Front center speaker output (-) - terminal 12 X2
    • Left rear subwoofer speaker output (+) - terminal 5 X1
    • Left rear subwoofer speaker output (-) - terminal 6 X1
    • Right front speaker output (+) - terminal 7 X1
    • Right front speaker output (-) - terminal 3 X1
    • Left front speaker output (+) - terminal 1 X1
    • Left front speaker output (-) - terminal 2 X1
    • Right front speaker output (+) - terminal 7 X1
    • Right front speaker output (-) - terminal 3 X1
    • Left rear midrange speaker output (+) - terminal 11 X2
    • Left rear midrange speaker output (-) - terminal 10 X2
    • If greater than the specified range, test both circuits of the affected speaker for a short to voltage.
  3. Radio ON, test for infinite resistance between the appropriate signal circuit terminal listed below and ground:
    • Left front tweeter speaker output (+) - terminal 4 X2
    • Left front tweeter speaker output (-) - terminal 5 X2
    • Right front tweeter speaker output (+) - terminal 7 X2
    • Right front tweeter speaker output (-) - terminal 6 X2
    • Left rear speaker output (+) - terminal 16 X2
    • Left rear speaker output (-) - terminal 8 X2
    • Right rear speaker output (+) - terminal 15 X2
    • Right rear speaker output (-) - terminal 14 X2
    • Front center speaker output (+) - terminal 13 X2
    • Front center speaker output (-) - terminal 12 X2
    • Left rear subwoofer speaker output (+) - terminal 5 X1
    • Left rear subwoofer speaker output (-) - terminal 6 X1
    • Right front speaker output (+) - terminal 7 X1
    • Right front speaker output (-) - terminal 3 X1
    • Left front speaker output (+) - terminal 1 X1
    • Left front speaker output (-) - terminal 2 X1
    • Right front speaker output (+) - terminal 7 X1
    • Right front speaker output (-) - terminal 3 X1
    • Left rear midrange speaker output (+) - terminal 11 X2
    • Left rear midrange speaker output (-) - terminal 10 X2
    • If less than the specified value, test both circuits of the affected speaker for a short to ground.
  4. If all circuits test normal, reconnect all harness connectors at the amplifier.
  5. Ignition OFF, disconnect the appropriate speaker.
  6. Radio ON, test for 5.0-7.5 V between the signal circuit terminals and ground.
    • If less then the specified range test the circuit for an open/high resistance. If the circuit tests normal, replace the amplifier.
    • If greater then the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the amplifier.
  7. If the circuit tests normal, replace the appropriate speaker.

Powered Subwoofer Malfunction RPO UQS

  1. Disconnect the harness connector at the inoperative subwoofer.
  2. Ignition ON, test for less than 1 V between the ground circuit terminal B and ground.
    • If greater than the specified range, test the ground circuit for an short to voltage.
  3. Ignition OFF, test for less than 10 Ω between the ground circuit terminal B and ground
    • If greater than specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, test for B+ between circuit terminal A and ground.
    • If less then the specified value, test the B+ circuit for a short to ground or an open/high resistance.
  5. Radio ON, test for B+ between the radio audio mute signal circuit terminal C and ground.
    • If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the amplifier.
  6. Radio ON, test for 5.0-7.5 V between the signal circuit terminal E and ground.
    • If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the audio amplifier.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the audio amplifier.
  7. Test for 5.0-7.5 V between the signal circuit terminal D and ground.
    • If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the audio amplifier.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the audio amplifier.
  8. If all circuits test normal, replace the subwoofer.
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