LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Hummer >> 2008 >> H3 Base, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 491 (Cellular System, Entertainment System And Navigation System) >> Diagnostic Information and Procedures >> Speaker Malfunction >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

WARNING: This page is about a different car, the 2010 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.

Amplifier Circuit Malfunction

  1. Ignition OFF, disconnect the X2 harness connector at the audio amplifier.
  2. Ignition OFF, test for less than 10 Ω between the ground circuit terminal 2 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, test for B+ on the B+ circuit terminal 1 and ground.
    • If less than the specified value, test the B+ circuit for a short to ground or an open/high resistance.
  4. Radio ON, test for 0.6-1.0V between the amplifier control circuit terminal 11 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.
    • If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the radio.
  5. If all circuits test normal, replace the audio amplifier.

Speaker Circuit Malfunction YQ2

  1. Disconnect the X1 harness connector at the audio amplifier.
  2. Radio ON, test for 5.0-7.5V between the appropriate audio signal circuit terminal listed below and ground.
    • Left front low level (+) - terminal 1
    • Left front low level (-) - terminal 17
    • Right front low level (+) - terminal 2
    • Right front low level (-) - terminal 18
    • Left rear low level (+) - terminal 5
    • Left rear low level (-) - terminal 21
    • Right rear low level (+) - terminal 6
    • Right rear low level (-) - terminal 22
    • Center channel low level (+) - terminal 3
    • Center channel and subwoofer low level audio common (-) - terminal 19
    • Sub woofer low level (+) - terminal 4
    • 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 radio.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
  3. Ignition OFF, connect the X1 harness connector at the audio amplifier.
  4. Disconnect the X2 harness connector at the audio amplifier.
  5. Ignition ON, test for less than 1V between the appropriate speaker signal circuit terminal listed below and ground.
    • Front center speaker output (+) - terminal 9
    • Front center speaker output (-) - terminal 21
    • Left front woofer speaker output (+) - terminal 13
    • Left front woofer speaker output (-) - terminal 14
    • Right front woofer speaker output (+) - terminal 11
    • Right front woofer speaker output (-) - terminal 12
    • Left rear midrange speaker output (+) - terminal 7
    • Left rear midrange speaker output (-) - terminal 19
    • Right rear midrange speaker output (+) - terminal 8
    • Right rear midrange speaker output (-) - terminal 20
    • Rear subwoofer speaker output (+) - terminal 4
    • Rear subwoofer speaker output (-) - terminal 16
    • If greater than the specified range, test the signal circuit for a short to voltage.
  6. Ignition OFF, test for infinite resistance between the appropriate terminal listed below and ground.
    • Front center speaker output (+) - terminal 9
    • Front center speaker output (-) - terminal 21
    • Left front woofer speaker output (+) - terminal 13
    • Left front woofer speaker output (-) - terminal 14
    • Right front woofer speaker output (+) - terminal 11
    • Right front woofer speaker output (-) - terminal 12
    • Left rear midrange speaker output (+) - terminal 7
    • Left rear midrange speaker output (-) - terminal 19
    • Right rear midrange speaker output (+) - terminal 8
    • Right rear midrange speaker output (-) - terminal 20
    • Rear subwoofer speaker output (+) - terminal 4
    • Rear subwoofer speaker output (-) - terminal 16
    • If less than the specified value, test the signal circuit for a short to ground.
  7. Reconnect all harness connectors at the amplifier. Disconnect the harness connector at the appropriate speaker.
  8. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminals listed below and ground.
    • Center console speaker- terminal A and B
    • Center I/P speaker- terminal A and B
    • Driver seat left- terminal A and B
    • Driver seat right- terminal A and B
    • Front tweeters- terminal A and B
    • Front speakers- terminal A and B
    • Front subwoofer speakers- terminal D and E
    • Rear compartment speakers - terminal A and B
    • Rear speakers- terminal A and B
    • Passenger seat left speaker - terminal A and B
    • Passenger seat right speaker - terminal A and B
    • Rear subwoofer - terminal Dand E
    • If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the amplifier.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the amplifier.
  9. If all circuits test normal, replace the speaker.

Speaker Circuit Malfunction YQ4 YQ6 YQ7

  1. Disconnect the X1 harness connector at the audio amplifier.
  2. Radio ON, test for 5.0-7.5V between the appropriate audio signal circuit terminal listed below and ground.
    • Left front low level (+) - terminal 1
    • Left front low level (-) - terminal 17
    • Right front low level (+) - terminal 2
    • Right front low level (-) - terminal 18
    • Left rear low level (+) - terminal 5
    • Left rear low level (-) - terminal 21
    • Right rear low level (+) - terminal 6
    • Right rear low level (-) - terminal 22
    • Center channel low level (+) - terminal 3
    • Center channel and subwoofer low level audio common (-) - terminal 19
    • Sub woofer low level (+) - terminal 4
    • 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 radio.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
  3. Ignition OFF, connect the X1 harness connector at the audio amplifier.
  4. Disconnect the X2 harness connector at the audio amplifier.
  5. Ignition ON, test for less than 1V between the appropriate speaker signal circuit terminal listed below and ground.
    • Front center speaker output (+) - terminal 6
    • Front center speaker output (-) - terminal 18
    • Center console speaker output (+) - terminal 3
    • Center console speaker output (-) - terminal 15
    • Left front speaker output (+) - terminal 7
    • Left front speaker output (-) - terminal 19
    • Left front woofer speaker output (+) - terminal 27
    • Left front woofer speaker output (-) - terminal 35
    • Left front seat left speaker output (+) - terminal 10
    • Left front seat left speaker output (-) - terminal 22
    • Left front seat right speaker output (+) - terminal 23
    • Left front seat right speaker output (-) - terminal 31
    • Right front speaker output (+) - terminal 8
    • Right front speaker output (-) - terminal 20
    • Right front speaker woofer output (+) - terminal 28
    • Right front speaker woofer output (-) - terminal 36
    • Right front seat left speaker output (+) - terminal 9
    • Right front seat left speaker output (-) - terminal 21
    • Right front seat right speaker output (+) - terminal 24
    • Right front seat right speaker output (-) - terminal 32
    • Left rear midrange speaker output (+) - terminal 13
    • Left rear midrange speaker output (-) - terminal 14
    • Left rear shelf speaker output (+) - terminal 4
    • Left rear shelf speaker output (-) - terminal 16
    • Right rear midrange speaker output (+) - terminal 11
    • Right rear midrange speaker output (-) - terminal 12
    • Right rear shelf speaker output (+) - terminal 5
    • Right rear shelf speaker output (-) - terminal 17
    • Rear subwoofer speaker output (+) - terminal 29
    • Rear subwoofer speaker output (-) - terminal 37
    • If greater than the specified range, test the signal circuit for a short to voltage.
  6. Ignition OFF, test for infinite resistance between the appropriate terminal listed below and ground.
    • Front center speaker output (+) - terminal 6
    • Front center speaker output (-) - terminal 18
    • Center console speaker output (+) - terminal 3
    • Center console speaker output (-) - terminal 15
    • Left front speaker output (+) - terminal 7
    • Left front speaker output (-) - terminal 19
    • Left front woofer speaker output (+) - terminal 27
    • Left front woofer speaker output (-) - terminal 35
    • Left front seat left speaker output (+) - terminal 10
    • Left front seat left speaker output (-) - terminal 22
    • Left front seat right speaker output (+) - terminal 23
    • Left front seat right speaker output (-) - terminal 31
    • Right front speaker output (+) - terminal 8
    • Right front speaker output (-) - terminal 20
    • Right front speaker woofer output (+) - terminal 28
    • Right front speaker woofer output (-) - terminal 36
    • Right front seat left speaker output (+) - terminal 9
    • Right front seat left speaker output (-) - terminal 21
    • Right front seat right speaker output (+) - terminal 24
    • Right front seat right speaker output (-) - terminal 32
    • Left rear midrange speaker output (+) - terminal 13
    • Left rear midrange speaker output (-) - terminal 14
    • Left rear shelf speaker output (+) - terminal 4
    • Left rear shelf speaker output (-) - terminal 16
    • Right rear midrange speaker output (+) - terminal 11
    • Right rear midrange speaker output (-) - terminal 12
    • Right rear shelf speaker output (+) - terminal 5
    • Right rear shelf speaker output (-) - terminal 17
    • Rear subwoofer speaker output (+) - terminal 29
    • Rear subwoofer speaker output (-) - terminal 37
    • If less than the specified value, test the signal circuit for a short to ground.
  7. Reconnect all harness connectors at the amplifier. Disconnect the harness connector at the appropriate speaker.
  8. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminals listed below and ground.
    • Center console speaker- terminal A and B
    • Center I/P speaker- terminal A and B
    • Driver seat left- terminal A and B
    • Driver seat right- terminal A and B
    • Front tweeters- terminal A and B
    • Front speakers- terminal A and B
    • Front subwoofer speakers- terminal D and E
    • Rear compartment speakers - terminal A and B
    • Rear speakers- terminal A and B
    • Passenger seat left speaker - terminal A and B
    • Passenger seat right speaker - terminal A and B
    • Rear subwoofer - terminal D and E
    • If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the amplifier.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the amplifier.
  9. If all circuits test normal, replace the speaker.
scientia non olet · About LEMON Manuals