GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Accessory Voltage

1

1

--

--

Remote Infra Red Signal (+)

2

2

2

--

Remote Infra Red Signal (-)

2

2

2

--

Infra Red Module Ground

--

1

--

--

1. Infra Red Module Inoperative -- remote control inoperative.

2. Remote control inoperative.

Circuit Description

The infrared transmitter is powered by the retained accessory power (RAP) relay. When a key on the remote is pressed, the remote control sends an infrared message to the infrared transmitter. The infrared transmitter will convert these infrared signals into a frequency and send that message to the radio via the remote infrared signal circuits (+) and (-).

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Entertainment/Communication Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Scan Tool Data List

Circuit/System Testing

Important: Test or replace the remote batteries before performing the circuit/system test.

  1. Ignition OFF, disconnect the harness connector at the infrared transmitter.
  2. Ignition OFF, test for less than 5.0 Ω between the ground circuit terminal 12 and ground.
  3. If greater than specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, test for B+ between the accessory voltage circuit terminal 4 and ground.
  5. If less than specified value, test the accessory voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear seat audio module.
  6. DVD playing, test for 0.75-2 volts between the remote infra red signal (+) circuit terminal 8 and ground.
  7. If less than 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 specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
  8. Test for less than 1 volt between the remote infra red signal (-) circuit terminal 16 and ground.
  9. If greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
  10. Ignition OFF, reconnect the harness connector at the infrared transmitter, disconnect the X3 harness connector at the radio.
  11. Ignition ON, DVD playing, test for 4-5.5 mV AC between the remote infra red signal (+) circuit terminal 5 and ground.
  12. If less than specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the infrared transmitter.
    If greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the infrared transmitter.
  13. Ignition ON, DVD playing, test for 4-6 mV AC between the remote infra red signal (-) circuit terminal 13 and ground.
  14. If less than specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the infrared transmitter.
    If greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the infrared transmitter.
  15. Ignition ON, DVD playing, press any button on the remote control aimed at the infrared transmitter. Test for 300-330 MHz between the remote infra red signal (+) circuit terminal 5 and ground.
  16. If not within the specified range, replace the remote control.
  17. If all circuits test normal, replace the radio.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for radio replacement, setup, and programming