Inspection Procedure 13

Inspection Procedure 13: KOS timer lock function does not work.

CAUTION:
Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.

OPERATION

After the door is unlocked with the keyless entry function, if no operation is performed, the door is locked when the time specified by a customization function has elapsed. However, an open signal from any door, key reminder switch OFF (with the key inserted) signal, or ignition push switch ON signal has been input to ETACS, the KOS timer will not operate.

PROBABLE CAUSES

- Malfunction of ETACS-ECU

- Malfunction of the door switches

DIAGNOSTIC PROCEDURE

Required Special Tools:

- MB991223: Harness Set

- MB992006: Extra Fine Probe

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.

- MB991827: M.U.T.-III USB Cable

- MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code.





(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

Connect scan tool MB991958. Refer to "How to connect scan tool (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."
(2)Turn the ignition switch to the "ON" position.
(3)Check whether the KOS-ECU related DTC is set.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the DTC set?

YES Diagnose the KOS-ECU. Refer to Keyless Operation System (KOS).

NO Go to Step 2.

STEP 2. Retest the system.

Check that the KOS timer lock function operates.

Q. Is the check result normal?

YES Intermittent malfunction How to Cope With Intermittent Malfunctions).
NO Perform troubleshooting for each door switch Symptom ChartInput signal chart ).