11. Headlights Do Not Go Out-Lights ON, Key OFF For 3 Minutes

The headlights do not go out after the lighting switch is on and the ignition switch remains "OFF" for more than three minutes.

CIRCUIT OPERATION

TECHNICAL DESCRIPTION
If the lighting switch is on and the ignition switch remains "OFF" for more than three minutes, the ETACS-ECU sends a 'light off' signal to the FRONT-ECU.

TROUBLESHOOTING HINTS
- Malfunction of the ETACS-ECU
- Malfunction of the ignition switch
- Damaged harness wire or connector

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

CAUTION: To prevent damage to scan tool MB991502, make sure that the ignition switch is "OFF" before connecting or disconnecting the scan tool.

STEP 1. Check input signal from the ignition switch, using either the scan tool or a voltmeter.




- Using scan tool MB991502
1. Connect Scan Tool MB991502 to the data link connector.
2. Check that the tone alarm of the scan tool sounds when the ignition key is moved from the "LOCK" position to the "ON" position.
If the tone alarm of the scan tool does not sound, input signal from the ignition switch is faulty. Go to Step 2.
If the tone alarm of the scan tool sounds, input signal from the ignition switch is normal. Go to Step 6.




- Using a voltmeter
1. Use special tool MB991529 to connect a voltmeter between ground terminal 4 or 5 and ETACS-ECU terminal 9 of the data link connector.
2. If a voltmeter indicator deflects once when the ignition key is moved from the "LOCK" position to the "ON" position, the ETACS-ECU input signal for that ignition switch is normal.
If the input signal of the ignition switch is not normal, go to Step 2.
If the input signal of the ignition switch is normal, go to Step 6.




STEP 2. Check the ETACS-ECU power supply.
1. Remove the instrument panel side cover.
2. Disconnect ETACS-ECU connector C-86.
3. Turn the ignition switch "ON."
4. Measure voltage between ETACS-ECU connector C-86 terminal number 11 and ground.
- Voltage should be approximately 12 volts (battery positive voltage).
If approximately 12 volts, repair the ETACS-ECU. Check that the malfunction is eliminated.
If not approximately 12 volts, go to Step 3.

STEP 3. Check the ignition switch continuity.
1. Remove the column covers, lower and upper.
2. Disconnect the wiring connector from the ignition switch.







3. Operate the ignition switch, and check continuity between the terminals.
If continuity, go to Step 4.
If no continuity, replace the switch. Check that the malfunction is eliminated.




STEP 4. Check ETACS-ECU connector C-86 and the ignition switch for damage
If harness connector C-86 is damaged, repair or replace it.
Refer to Harness Connector Inspection. If harness connector C-86 is in good condition, go to Step 5.




STEP 5. Check the harness wires between ETACS-ECU C-86 and the ignition switch.
If any harness wires between ETACS-ECU C-86 and the ignition switch are damaged, repair them.
Refer to Harness Connector Inspection. If the harness wires are in good condition, repair the ETACS-ECU and go to Step 6.

STEP 6. Check symptoms.
Confirm that the headlight auto off system operates normally.