Inspection Procedure E-2

Keyless Entry System: The dome light, hazard warning lights (turn-signal lights) and horn do not operate through the answer back function.

CIRCUIT OPERATION
The ETACS-ECU operates the following functions when it receives a lock or unlock signal from the transmitter:
- Dome light answer back function
- Hazard warning lights answer back function
- Horn answer back function

TECHNICAL DESCRIPTION (COMMENT)
The hazard warning lights or horn answer back functions can be disabled. However, the dome light answer back function can be disabled.

TROUBLESHOOTING HINTS
- The hazard warning lights (turn-signal lights) may be defective.
- The horn may be defective.
- The dome light may be defective.
- The ETACS-ECU may be defective.
- The wiring harness may be damaged or the connectors) may have loose, corroded or damaged terminals, or terminals pushed back in the connector

Required Special Tools:
- MB991223: Harness Set
- MB991502: Scan Tool (MUT-II)

STEP 1. Verify the keyless entry system.

Q: Does the keyless entry system work normally?

YES: Go to Step 2.

NO: Refer to Inspection Procedure E-1 "Keyless entry system does network normally."

STEP 2. Verify the answer back adjustment function.
Check the answer back functions. (Refer to Keyless Entry System - On-vehicle Service - Enabling/disabling the Answer back Function.)

Q: Does the answer back function work normally?

YES: No action is necessary and testing is complete.

NO: Go to Step 3.

STEP 3. Verify the trouble symptom.

Q: Which answer back function is defective?

Only the dome light : Go to Step 4.
Only the hazard warning lights (turn-signal lights): Go to Step 5.
All functions do not work [dome light, hazard warning lights (turn-signal lights) and horn]. : Replace the ETACS-ECU. Verify that the answer back functions work normally.

STEP 4. Verify the dome light.

Q: Does the dome light illuminate normally?

YES: Replace the ETACS-ECU. Verify that the answer back functions work normally.

NO: Refer to Inspection Procedure M-1 "Dome light does not illuminate."

STEP 5. Verify the hazard warning light.

Q: Do the hazard warning lights work normally?

YES: Replace the ETACS-ECU. Verify that the answer back functions work normally.

NO: Refer to Inspection Procedure K-2 "Hazard warning lights do not flash when the hazard warning light switch is turned on."