Inspection Procedure 2: Check the satellite radio tuner power supply circuit: Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB992006: Extra Fine Probe

1. STEP 1. Check satellite radio tuner connectors C-150 for loose, corroded or damaged terminals, or terminals pushed back in the connector  .

   Q: Is satellite radio tuner connectors C-150 in good condition? 

   • YES:  Go to Step 2.
   • NO:  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION .
2. STEP 2. Check the ground circuit to the satellite radio tuner. Measure the resistance at satellite radio tuner connectors C-150  .
   1. Disconnect satellite radio tuner connector C-150 and measure the resistance available at the wiring harness side of the connector.
   2. Measure the resistance value between satellite radio tuner connector C-150 terminal 8 and ground.
      • The resistance should be 2 ohms or less.
      Fig 1: Measuring Resistance Value Between Satellite Radio Tuner Connector C-150 Terminal 8 And Ground

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

   Q: Is the measured resistance 2 ohms or less? 

   • YES:  Go to  Step 4.
   • NO:  Go to Step 3.
3. STEP 3. Check the wiring harness between satellite radio tuner connector C-150 (terminal 8) and ground  .
   • Check the ground wire for open circuit.

   Q: Is the wiring harness between satellite radio tuner connector C-150 (terminal 8) and ground in good condition? 

   • YES:  No action is necessary and testing is complete.
   • NO:  The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.
4. STEP 4. Check the power supply circuit to the satellite radio tuner. Measure the voltage at satellite radio tuner connector C-150. 
   1. Disconnect the connector, and measure at the wiring harness-side connector.
   2. Measure the voltage between terminal 1 and ground.

      OK: Battery positive voltage 

      Fig 2: Measuring Voltage Between Terminal 1 And Ground

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

   Q: Is the measured voltage battery positive voltage? 

   • YES:  Go to  Step 6.
   • NO:  Go to Step 5.
5. STEP 5. Check the wiring harness between satellite radio tuner connector C-150 (terminal 1) and fusible link (36)  .
   • Check the power supply line for open circuit and short circuit.
   NOTE: Also check ETACS-ECU connectors C-307 and C-317 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If ETACS-ECU connector C-307 or C-317 is damaged, repair or replace the connector. Refer to HARNESS CONNECTOR INSPECTION .

   Q: Is the wiring harness between satellite radio tuner connector C-150 (terminal 1) and fusible link (36) in good condition? 

   • YES:  No action is necessary and testing is complete.
   • NO:  The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. The system should communicate with the satellite radio tuner normally.
6. STEP 6. Retest the system 

   Check if the satellite radio tuner works normally.

   Q: Is the check result normal? 

   • YES:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
   • NO:  Replace the satellite radio tuner.