Inspection Procedure O-1

The ignition switch (ACC) signal is not sent to the ETACS-ECU.

Ignition Switch (ACC) Input Circuit:

CIRCUIT OPERATION
The ETACS-ECU operates various functions according to the input signal from the ignition switch (ACC).

TECHNICAL DESCRIPTION (COMMENT)
The ignition switch (ACC) input signal is used to operate the windshield wiper and washer. If the signal fails, windshield wiper and washer will not work normally.

NOTE: The windshield wiper and washer works normally if a normal ignition switch (ACC) signal is sent from the ignition switch directly to the front-ECU.

TROUBLESHOOTING HINTS
- 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 (ACC) circuit at the ETACS-ECU connector C-311.

1. Disconnect the ETACS-ECU connector C-311 and measure at the junction block side.
2. Turn the ignition switch to the "ACC" position.




3. Measure the voltage between terminal 7 and ground.

Q: Is the voltage approximately 12 volts (battery positive voltage)?

YES: Replace the ETACS-ECU. The ignition switch (ACC) input signal should be able to be checked and the windshield wiper and washer should work normally.
NO: Go to Step 2.




STEP 2. Check ETACS-ECU connector C-311 for damage.

Q: Is ETACS-ECU connector C-311 in good condition?

YES: Go to Step 3.
NO: Repair or replace it. Refer to Harness Connector Inspection. The ignition switch (ACC) input signal should be able to be checked and the windshield wiper and washer should work normally.




STEP 3. Check the harness wires between ETACS-ECU connector C-311 and ignition switch (ACC).






NOTE: After checking junction block connector C-301, check the wires. If junction block connector C-301 is damaged, repair or replace it. Refer to Harness Connector Inspection.

Q: Are the harness wires between ETACS-ECU connector C-311 and ignition switch (ACC) in good condition?

YES: There is no action to be taken.
NO: Repair them. The ignition switch (ACC) input signal should be able to be checked and the windshield wiper and washer should work normally.