Inspection Procedure 4: Audio illuminations does not work normally: Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB992006: Extra Fine Probe

1. STEP 1. Check that the taillights illuminate  .

   Q: Is the check result normal? 

   • YES:  Go to Step 2.
   • NO:  Diagnose the taillights. (Refer to TROUBLE SYMPTOM CHART .)
2. STEP 2. Check the illumination  .

   When the taillights are turned on, check whether the illumination other than the radio and CD player is turned on.

   Q: Is the check result normal? 

   • YES:  Go to Step 3.
   • NO:  Replace the A/C control panel.
3. STEP 3. Check radio and CD player connector C-104 and A/C control panel connector C-146 for loose, corroded or damaged terminals, or terminals pushed back in the connector  .

   Q: Are radio and CD player connector C-104 and A/C control panel connector C-146 in good condition? 

   • YES:  Go to Step 4.
   • NO:  Repair the connector concerned.
4. STEP 4. Check the wiring harness between radio and CD player connector C-104 (terminal 29) and A/C control panel connector C-146 (terminal 18)  .
   • Check the wiring harness for open circuit and short circuit.

   Q: Is the wiring harness between radio and CD player connector C-104 (terminal 29) and A/C control panel connector C-146 (terminal 18) in good condition? 

   • YES:  Go to Step 5.
   • NO:  Repair the wiring harness.
5. STEP 5. Retest the system 

   When the taillights illuminate, check that the illumination of the radio and CD player is switched from day mode to night mode.

   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 radio and CD player.