Inspection Procedure J-1
Flasher Timer: Turn-signal Lights does not Flash when the Turn-signal Light Switch is Turned On.
Turn-signal Light Power Supply Circuit:
CIRCUIT OPERATION
- The turn-signal light switch sends a signal through the column-ECU (incorporated in the column switch) to the ETACS-ECU. If the column- ECU sends a turn-signal light switch "ON" signal to the ETACS-ECU, the ETACS-ECU turns on the flasher timer (incorporated in the ETACS-ECU), thus causing the turn-signal lights to flash.
- The ETACS-ECU operates the turn-signal lights according to the following signals:
- Ignition switch (IG1): ON
- Turn-signal light switch: ON
- The ETACS-ECU flashes the turn-signal lights under the following conditions:
- Ignition key: "ON" position
- Turn-signal light switch: Left or right turn-signal position
TECHNICAL DESCRIPTION (COMMENT)
Is the turn-signal lights do not flash normally, the input circuits from the switches described in "CIRCUIT OPERATION" or the ETACS-ECU may be defective. If the hazard warning lights do not flash, the power supply line to the ETACS-ECU (dedicated to the turn-signal lights) may be defective.
TROUBLESHOOTING HINTS
- Malfunction of column switch (turn-signal light and lighting switch)
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors
DIAGNOSIS
Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
- MB991862: SWS monitor kit
STEP 1. Check the hazard warning light.
Q: Do the hazard warning lights work normally?
YES: Go to Step 7.
NO: Go to Step 2.
STEP 2. Check the turn-signal lights.
Q: Does either of the turn-signal lights illuminate?
YES: (illuminates at only one side): Go to Step 3.
NO: (do not illuminate at all): Go to Step 4.
STEP 3. Check ETACS-ECU connector C-95, junction block connectors C-77, C-84 and C-88 for damage.
Q: Are ETACS-ECU connector C-95, junction block connectors C-77, C-84 and C-88 in good condition?
YES: Replace the ETACS-ECU. Check that the turn-signal lights illuminate normally.
NO: Repair or replace the connector. Refer to Harness Connector Inspection. Check that the turn-signal lights illuminate normally.
STEP 4. Check at ETACS-ECU connector C-95 in order to check the power supply circuit to the ETACS-ECU (battery power supply).
1. Disconnect ETACS-ECU connector C-95, and measure at the junction block side.
2. Measure the voltage between terminal 11 and ground.
- The measured value should be approximately 12 volts (battery positive voltage).
Q: Does the measured voltage correspond with this range?
YES: Replace the ETACS-ECU. Check that the turn-signal lights illuminate normally.
NO: Go to Step 5.
STEP 5. Check ETACS-ECU connector C-95 for damage.
Q: Is ETACS-ECU connector C-95 in good condition?
YES: Go to Step 6.
NO: Repair or replace the connector. Refer to Harness Connector Inspection. Check that the turn-signal lights illuminate normally.
STEP 6. Check the wiring harness between ETACS-ECU connector C-95 and the battery.
NOTE: Also check junction block connector C-88. If junction block connector C-88 is damaged, repair or replace the connector as described in Harness Connector Inspection.
Q: Is the wiring harness between ETACS-ECU connector C-95 and the battery in good condition?
YES: No action to be taken.
NO: Repair the wiring harness. Check that the turn-signal lights illuminate normally.
STEP 7. Check the input signal by using service data of the SWS monitor.
Check the input signals from the following switches:
- Ignition switch: ON
- Turn-signal light switch: RH
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502. Also connect SWS monitor kit MB991862 after turning on scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Connect SWS monitor kit MB991862 to the column switch connector.
3. Select "TURN SIGNAL - TURN-SIG.RH" (FUNCTION DIAG), and check that normal conditions are displayed on the items described in the table.
Q: Does the scan tool display the items "T/S RH SW" and "IG SW (IG1)" as normal condition?
YES: Replace the ETACS-ECU. Check that the turn-signal lights illuminate normally.
NO:
- Normal condition is not displayed "T/S RH SW: Refer to Inspection Procedure N-5 "ETACS-ECU does not receive any signal from the taillight switch, the headlight switch, the passing light switch, the dimmer switch, the turn-signal light switch or switch."
- Normal condition is not displayed "IG SW (IG1)": Refer to Inspection Procedure N-2 "ETACS-ECU does not receive a signal from the ignition switch (IG1)."