Inspection Procedure E-2

Keyless entry system: The interior lights, the hazard warning lights and the horn do not operate through the answerback function.

TECHNICAL DESCRIPTION (COMMENT)
The turn-signal light and the horn answerback functions can be selected by the driver's desire (can be deactivated). However, the interior lights answerback function can not be deactivated. If all of these devices do not operate through the answerback function, the ETACS-ECU may be defective.

TROUBLESHOOTING HINTS
- Malfunction of the turn-signal light
- Malfunction of the theft-alarm horn
- Malfunction of the interior lights
- 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 answerback set condition.
Activate the answerback functions. (Refer to Keyless Entry System - Enabling/disabling the Answerback Function)

Q: Does the answerback function work normally?

YES: There is no action to be taken.
NO: Go to Step 2.

STEP 2. Check trouble symptom.

Q: Which component(s) does not operate through the answerback?

Only the interior lights: Go to Step 3.
Only the hazard warning lights: Go to Step 4.
Only the horn: Go to Step 5.
None of the interior lights, the turn-signal lights, and the horn: Replace the ETACS-ECU. The answerback function should work normally.

STEP 3. Check the interior lights dimming function.

Q: Does the interior lights dimming function work normally?

YES: Replace the ETACS-ECU. The answerback function should work normally.
NO: Solve the problem first. Refer to Inspection Procedure M-1.

STEP 4. Check the hazard warning light operation.

Q: Do the hazard warning lights operate normally?

YES: Replace the ETACS-ECU. The answerback function should work normally.
NO: Solve the problem first. Refer to Inspection Procedure K-2.

STEP 5. Check the working of the horn by the theft-alarm system.

Q: Does the horn work normally by the theft-alarm system?

YES: Replace the ETACS-ECU. The answerback function should work normally.
NO: Solve the problem first. Refer to Inspection Procedure N-2.