Inspection Procedure O-1

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 following devices. If the signal fails, these devices will not work normally.
- Windshield wiper and washer
- Rear wiper and washer

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-114.
1. Disconnect the ETACS-ECU connector C-114 and measure at the junction block side.
2. Turn the ignition switch to "ACC" position.
3. Voltage between terminal 7 and ground.
- Voltage should be approximately 12 volts (battery positive voltage).
If not approximately 12 volts, go to Step 2.
If approximately 12 volts, replace the ETACS-ECU. The ignition switch (ACC) input signal should be able to be checked and the functions, which are described in the "Technical Description (comment)," should work normally.

STEP 2. Check the ETACS-ECU connector C-114 for damage.
If the ETACS-ECU connector C-114 is damaged, repair or replace it. Refer to Harness Connector Inspection.
The ignition switch (ACC) input signal should be able to be checked and the functions, which are described in the "Technical Description (comment)," should work normally.
If the connector is in good condition, go to Step 3.

STEP 3. Check the harness wires between ETACS-ECU connector C-114 and ignition switch (ACC).

NOTE: After checking junction block connector C-101, check the wires. If junction block connector C-101 is damaged, repair or replace it. Refer to Harness Connector Inspection.

If the harness wires between ETACS-ECU connector C-114 and ignition switch (ACC) is damaged, repair them. The ignition switch (ACC) input signal should be able to be checked and the functions, which are described in the "Technical Description (comment)," should work normally.