Inspection Procedure 5: Audio Illuminations Does Not Work Normally: Diagnosis
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
- STEP 1. Operation check of the center panel unit
Operate the audio control switch of the center panel unit, and check if the audio operates normally.
Q: Is the check result normal?
YES : Go to Step 2.
NO : Refer to INSPECTION PROCEDURE 4 "THE AUDIO DOES NOT OPERATE NORMALLY BY OPERATING THE RADIO AND CD PLAYER OF THE CENTER PANEL UNIT." .
- STEP 2. Check the combination meter.
Check whether the combination meter works normally.
Q: Is the check result normal?
YES : Go to Step 3.
NO : Diagnose the combination meter (Refer to DIAGNOSTIC TROUBLE CODE CHART ).
- STEP 3. Using scan tool MB991958, read the combination meter diagnostic trouble code.
Check again if the DTC is set to the combination meter.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.- Connect scan tool MB991958. Refer to "HOW TO CONNECT SCAN TOOL .".
- Turn the ignition switch to the "ON" position.
- Check for combination meter DTCs.
- Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the combination meter (Refer to DIAGNOSTIC TROUBLE CODE CHART ).
NO : Go to Step 4.
- STEP 4. Check center panel unit connector C-124 and combination meter connector C-04 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are center panel unit connector C-124 and combination meter connector C-04 in good condition?
YES : Go to Step 5.
NO : Repair the connector concerned.
- STEP 5. Check the wiring harness between center panel unit connector C-124 (terminal 10, 16) and combination meter connector C-04 (terminal 22, 23).
- Check the communication lines for open circuit and short circuit.
NOTE: Also check A/C control panel connector C-123 and joint connector C-101 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If A/C control panel connector C-123 and joint connector C-101 is damaged, repair or replace the connector as described in HARNESS CONNECTOR INSPECTION .Q: Is the wiring harness between center panel unit connector C-124 (terminal 10, 16) and combination meter connector C-04 (terminal 22, 23) in good condition?
YES : Go to Step 6.
NO : Repair the wiring harness.
- STEP 6. Check radio and CD player connector C-109 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is radio and CD player connector C-109 in good condition?
YES : Go to Step 7.
NO : Repair the connector concerned.
- STEP 7. Check the wiring harness between center panel unit connector C-124 (terminal 4) and radio and CD player connector C-109 (terminal 9).
- Check the communication lines for open circuit and short circuit.
Q: Is the wiring harness between center panel unit connector C-124 (terminal 4) and radio and CD player connector C-109 (terminal 9) in good condition?
YES : Go to Step 8.
NO : Repair the wiring harness.
- STEP 8. Replace the center panel unit temporarily, and check the trouble symptom.
Replace the center panel unit temporarily, and check that the audio illumination works normally.
Q: Is the check result normal?
YES : Replace the center panel unit.
NO : Replace the radio and CD player.