Inspection Procedure 3: Steering wheel audio remote control switch illumination does not come on: Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB992006: Extra Fine Probe

1. STEP 1. Check the combination meter. 

   Check whether the combination meter works normally.

   Q: Does the combination meter operate normally? 

   • YES:  Go to Step 2.
   • NO:  Diagnose the combination meter (Refer to DIAGNOSTIC TROUBLE CODE CHART ).
2. STEP 2. Check steering wheel audio remote control switch connector C-202 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is steering wheel audio remote control switch connector C-202 in good condition? 

   • YES:  Go to Step 3.
   • NO:  Repair or replace the damaged component (Refer to HARNESS CONNECTOR INSPECTION ).
3. STEP 3. Check the wiring harness between steering wheel audio remote control switch connector C-202 (terminal 5) and ground. 
   • Check the ground wire for open circuit.

   Q: Is the wiring harness between steering wheel audio remote control switch connector C-202 (terminal 5) and ground in good condition? 

   • YES:  Go to Step 4.
   • 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 clock spring connectors C-204 and C-205 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Are clock spring connectors C-204 and C-205 in good condition? 

   • YES:  Go to Step 5.
   • NO:  Repair or replace the damaged component (Refer to HARNESS CONNECTOR INSPECTION ).
5. STEP 5. Check the clock spring. 

   Check whether the clock spring is in good condition (Refer to DRIVER'S AIR BAG MODULE AND CLOCK SPRING < RALLIART > < Except RALLIART > or < RALLIART > ).

   Q: Is the check result normal? 

   • YES:  Go to Step 6.
   • NO:  Replace the clock spring.
6. STEP 6. Check the wiring harness between steering wheel audio remote control switch connector C-202 (terminal 1) and clock spring connector C-204 (terminal 1). 
   • Check the power supply line for open circuit and short circuit.

   Q: Is the wiring harness between steering wheel audio remote control switch connector C-202 (terminal 1) and clock spring connector C-204 (terminal 1) in good condition? 

   • YES:  Go to Step 7.
   • 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.
7. STEP 7. Check combination meter connector C-04 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is combination meter connector C-04 in good condition? 

   • YES:  Go to Step 8.
   • NO:  Repair or replace the damaged component (Refer to HARNESS CONNECTOR INSPECTION ).
8. STEP 8. Check the wiring harness between combination meter connector C-04 (terminal 23) and clock spring connector C-205 (terminal 6). 
   • Check the power supply line for open circuit and short circuit.

   Q: Is the wiring harness between combination meter connector C-04 (terminal 23) and clock spring connector C-205 (terminal 6) in good condition? 

   • YES:  Go to Step 9.
   • 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.
9. STEP 9. Retest the system 

   Check whether the illumination of the steering wheel audio remote control switch comes on normally.

   Q: Doe the illumination of the steering wheel audio remote control switch comes on normally? 

   • YES:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
   • NO:  Replace the steering wheel audio remote control switch.