Circuit/System Testing

Digital Radio Antenna Circuit Malfunction

1. Ignition OFF, disconnect the appropriate digital radio antenna coax from the digital radio receiver (DRR). Connect the EL-48028  to the DRR. See Special Tools .
2. Ignition ON, radio tuned to XM, verify XM reception is clear and uninterrupted.
   • If reception is not clear, replace the DRR.
3. Ignition OFF, reconnect the antenna coax to the DRR, disconnect the digital radio antenna coax from the appropriate digital radio antenna.
4. Ignition ON, test for 4.5-5.5 volts between the antenna coax center terminal and the coax outer shield.
   • If not within the specified range, replace the antenna coax.
5. If all circuits test normal, replace the appropriate digital radio antenna.

Digital Radio Output Signal Circuit Malfunction

1. Ignition OFF, disconnect the X1 harness connector at the CD changer.
2. Ignition ON, radio ON and tuned to XM, test for a varying mV AC voltage reading between the following signal circuit terminals listed below and ground.
   • Left audio signal (+) - Connector X1, terminal 13
   • Right audio signal (+) - Connector X1, terminal 5
   • Audio common signal (-) - Connector X1, terminal 13
   • If the voltage reading is not as specified, test the signal circuit for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the DRR.
3. If all circuits test normal, replace the CD changer.