Inspection Procedure O-18

Column switch:
- The windshield mist wiper switch signal is not sent to the ETACS-ECU.
- The windshield intermittent wiper switch signal is not sent to the ETACS-ECU.
- The windshield low-speed wiper switch signal is not sent to the ETACS-ECU.
- The windshield high-speed wiper switch signal is not sent to the ETACS-ECU.
- The windshield washer switch signal is not sent to the ETACS-ECU.
- The rear wiper switch signal is not sent to the ETACS-ECU.
- The rear washer switch signal is not sent to the ETACS-ECU.

Windshield Wiper And Windshield Washer Switch Input Circuit:

CIRCUIT OPERATION
The ETACS-ECU uses the input signal from the column switch (windshield wiper and windshield washer switch) to operate various functions.

TECHNICAL DESCRIPTION (COMMENT)
The column switch (windshield wiper and windshield washer switch) input signal is used to operate the following devices. If the signal fails, these devices will not work normally.
- Windshield wiper and washer
- Rear wiper and washer
TROUBLESHOOTING HINTS
- Malfunction of the column switch (windshield wiper and windshield washer switch)
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

DIAGNOSIS
Required Special Tools:
MB991223: Test Harness Set
MB991502: Scan Tool (MUT-II)
MB991529: Diagnostic Trouble Code Check Harness

STEP 1. Check the ignition switch positions.
If a diagnostic trouble code sets when the ignition switch is at any of the positions, carry out the troubleshooting by referring to the Diagnostic Trouble Code Chart.
If a diagnostic trouble code does not set, go to Step 2.

STEP 2. Check the windshield wiper and windshield washer switch.
If the windshield wiper and windshield washer switch is damaged, replace it.

The input signal from the column switch (windshield wiper and washer switch) should be able to be checked and the functions, which are described in the "Technical Description (comment)," should work normally.

If the windshield wiper and windshield washer switch is in good condition, replace the column switch or ETACS-ECU. The input signal from the column switch (windshield wiper and washer switch) should be able to be checked and the functions, which are described in the "Technical Description (comment)," should work normally.