Inspection Procedure 2: Light intensity cannot be adjusted using sunshade illumination changeover switch: Diagnosis
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
- STEP 1. Check ETACS-ECU connector C-411, sunshade illumination changeover switch connector E-12 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is ETACS-ECU connector C-411, sunshade illumination changeover switch connector E-12 in good condition?
YES : Go to Step 2.
NO : Repair or replace the damaged component(s). (Refer to HARNESS CONNECTOR INSPECTION .)
- STEP 2. Check of sunshade illumination changeover switch
Check the sunshade illumination changeover switch. Refer to SUNSHADE ILLUMINATION REMOVAL AND INSTALLATION .
Q: Is the check result normal?
YES : Go to Step 3.
NO : Replace the sunshade illumination changeover switch.
- STEP 3. Resistance measurement at the E-12 sunshade illumination changeover switch connector
- Disconnect the connector, and measure at the wiring harness side.
- Measure the resistance between the sunshade illumination changeover switch connector E-12 terminal 1 and the body ground.
OK: The measured value should be continuity exists (2 ohms or less).
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 5.
NO : Go to Step 4.
- STEP 4. Check the wiring harness between the sunshade illumination changeover switch connector E-12 terminal 1 and the ground
- Check the ground wires for open circuit.
Q: Is the wiring harness between sunshade illumination changeover switch connector E-12 terminal 1 and ground in good condition?
YES : The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).
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.
- STEP 5. Check the wiring harness between ETACS-ECU connector C-411 terminal 17 and sunshade illumination changeover switch connector E-12 terminal 2 NOTE: Also check intermediate connector C-226 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-226 is damaged, repair or replace the connector as described in HARNESS CONNECTOR INSPECTION .
- Check the power supply lines for open and short circuit.
Q: Is the check result normal?
YES : Go to Step 6.
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.
- STEP 6. Retest the system
While the sunshade illumination is ON, check that the sunshade illumination brightness changes when the sunshade illumination changeover switch is pressed.
Q: Is the check result normal?
YES : The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).
NO : Replace the ETACS-ECU.