9. Headlights Do Not Work With Passing Switch
The headlights do not light up when the passing switch is operated.Passing Switch Circuit
TECHNICAL DESCRIPTION (COMMENT)
The passing switch (column switch) sends an incorrect signal to the ETACS-ECU.
TROUBLESHOOTING HINTS
- Malfunction of the column switch
- Malfunction of the FRONT-ECU
- Malfunction of the ETACS-ECU
- Damaged harness wire or connector
DIAGNOSIS
Required Special Tools:
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 the input signal from the passing 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 passing switch is ON.
If the tone alarm of the scan tool does not sound when the passing switch is ON, the passing switch is faulty. Go to Step 2.
If the tone alarm of the scan tool sounds when the passing switch is ON, the passing switch is normal.
Go to Step 3.
- 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 passing switch is ON, the ETACS-ECU input signal for that taillight switch circuit is normal.
If the input signal of the passing switch is not normal, go to Step 2.
If the tone alarm of the scan tool sounds when the passing switch ON, the passing switch is normal. Go to Step 3.
STEP 2. Check a diagnostic trouble code.
Connect scan tool MB991502 to the data link connector, and then check a diagnostic trouble code.
If diagnostic trouble code 11 is displayed, replace the ETACS-ECU, and check that the malfunction is eliminated.
If diagnostic trouble code 12 is displayed, replace the column switch, and check that the malfunction is eliminated.
If diagnostic trouble code 13 is displayed, replace the FRONT-ECU, and check that the malfunction is eliminated.
If diagnostic trouble code 21 is displayed, go to Step 3.
STEP 3. Check column switch C-60 connector and ETACS-ECU connector C-82 for damage.
If column switch connectors C-60, C-82 and ETACS-ECU connector are damaged, repair them. Refer to Harness Connector Inspection.
If the harness connectors are in good condition, go to Step 4.
STEP 4. Check harness wires between column switch C-60 and ETACS-ECU C-82.
If the harness wires between column switch C-60 and ETACS-ECU C-82 are damaged, repair them. Refer to Harness Connector Inspection. If the harness connectors are in good condition, go to Step 5.
STEP 5. Check column switch connector C-60 and FRONT-ECU connector A-09X for damage.
If the column switch connector C-60 and FRONT-ECU connector A-09X are damaged, repair them. Refer to Harness Connector Inspection.
If the harness connectors are in good condition, go to Step 6.
STEP 6. Check column switch connector C-60 and FRONT-ECU connector A-09X for damage.
If column switch connector C-60 and FRONT-ECU connector A-09X are damaged, repair them. Refer to Harness Connector Inspection.
If the harness connectors are in good condition, go to Step 7.
STEP 7. Check the harness wires between column switch C-60 and FRONT-ECU C-82.
If any harness wires between column switch C-60 and ETACS-ECU C-82 are damaged, repair them. Refer to Harness Connector Inspection.
If the harness connectors are in good condition, go to Step 8.
STEP 8. Check symptoms.
Confirm that the automatic reset function for headlight dimmer switch operates normally.