O - Charts

O-1: Check the Circuit (Power Supply Line) From the Battery to the ETACS-ECU.

CHECK THE CIRCUIT (POWER SUPPLY LINE) FROM BATTERY
Refer to Inspection Procedure A-1.

CIRCUIT OPERATION
The ETACS-ECU is always energized by the battery.

TECHNICAL DESCRIPTION (COMMENT)
If that power supply circuit is defective, the circuit flowing through the ignition switch (IG1) will function as a backup circuit. In this case, the following functions will not work when the ignition switch is at "LOCK" (OFF) position:
Ignition key reminder tone alarm function
- Light reminder tone alarm function
- Central door locking system
- Hazard warning light
- Dome light dimming function
- Theft-alarm system

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 battery circuit at the ETACS-ECU connector C-86.
1. Disconnect the ETACS-ECU connector C-86 and measure at the junction block side.

2. Measure the Voltage between terminal 2 and ground.

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

YES: Replace the ETACS-ECU. The functions, which are described in the "Technical Description (comment)," should work normally.

NO: Go to Step 2.

STEP 2. Check ETACS-ECU connector C-86 for damage.
Q: Is ETACS-ECU connector C-86 in good condition?

YES: Go to Step 3.

NO: Repair or replace it. Refer to Harness Connector Inspection. The functions, which are described in the "Technical Description (comment)," should work normally.

STEP 3. Check the harness wires between ETACS-ECU connector C-86 and battery.

NOTE: After checking junction block connector C-84 and intermediate connector C-66, check the wires. If junction block connector C-84 and intermediate connector C-66 are damaged, repair or replace them. Refer to Harness Connector Inspection.

Q: Are the harness wires between ETACS-ECU connector C-86 and battery in good condition?

YES: There is no action to be taken.

NO: Repair them. The functions, which are described in the "Technical Description (comment)," should work normally.