Inspection Procedure 4
Inspection Procedure 4: Tone alarm does not sound normally.
CAUTION:
Before replacing the combination meter, be sure to check that the power supply circuit, ground circuit, and communication circuit are normal.
TECHNICAL DESCRIPTION (COMMENT)
When the following signals are received via the CAN communication, the combination meter sounds the incorporated tone alarm according to the each pattern.
Seat belt reminder function
- Ignition switch ON signal
- Vehicle speed signal
- Driver's seat belt switch signal
- Front passenger's seat belt switch signal
Keyless operation key reminder tone alarm function (vehicles with KOS)
- Ignition switch OFF signal
- IG knob push switch ON signal
- Driver's door switch ON signal
Ignition key reminder tone alarm function (vehicles without KOS)
- Ignition switch OFF signal
- Key reminder switch OFF signal
- Driver's door switch ON signal
Light reminder tone alarm function
- Ignition switch OFF signal
- Lighting switch ON signal
- Driver's door switch ON signal
Door-ajar warning tone alarm function
- Ignition switch ON signal
- Any door switch or trunk lid latch ON signal
- Vehicle speed signal
Freeze warning tone alarm
- Ignition switch ON signal
- Ambient temperature signal
Parking brake reminder tone alarm function
- Ignition switch ON signal
- Parking brake switch ON signal
- Vehicle speed signal
Multi information display interrupt display tone alarm
- Display condition signal of information display from each warning (When there is a fixed tone alarm sounding pattern for each warning, that pattern has the priority.)
Meter information meter switch operation tone alarm
- ON signal for combination meter information meter switch
Turn-signal light tone alarm function
- Turn-signal light switch ON signal
Paddle shift cancel tone alarm, Theft-alarm function, ETACS-ECU function customize tone alarm, A/C operation tone alarm, audio operation tone alarm
- Sounding request signal from the ETACS-ECU
If the tone alarm does not sound normally, the connector(s) and wiring harness in the CAN bus lines, or each ECU or the combination meter may have a problem.
TROUBLESHOOTING HINTS
- The combination meter may be defective
- The each ECU may be defective
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
(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 the Scan Tool (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."
(2)Turn the ignition switch to the "ON" position.
(3)Diagnose the CAN bus line.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
Q. Is the CAN bus line found to be normal?
YES Go to Step 2.
NO Repair the CAN bus line CAN Bus Diagnostics Chart).
STEP 2. Using scan tool MB991958, read the combination meter diagnostic trouble code.
Check if DTC is set to the combination meter.
Q. Is the DTC set?
YES Troubleshoot the combination meter (Refer to Combination Meter).
NO Go to Step 3.
STEP 3. Using scan tool MB991958, read for any diagnostic trouble code.
Check if diagnostic trouble code is set to the engine control module, TC-SST-ECU, ASC-ECU, ETACS-ECU, WCM, KOS-ECU, audio and A/C-ECU.
Q. Is the DTC set to the any of the above?
YES [Set to the engine control module.] : Troubleshoot the engine control module Multiport Fuel Injection (MFI)).
YES [Set to the TC-SST-ECU.] : Troubleshoot the TC-SST Twin Clutch-Sportronic Shift Transmission (TC-SST)).
YES [Set to the ASC-ECU.] : Troubleshoot the ASC Active Stability Control System (ASC)).
YES [Set to the ETACS.] : Troubleshoot the ETACS (Refer to Electronic Time and Alarm Control System (ETACS)).
YES [Set to the WCM.] : Troubleshoot the WCM Wireless Control Module (WCM)).
YES [Set to the KOS.] : Troubleshoot the KOS Keyless Operation System (KOS)).
YES [Set to the audio.] : Troubleshoot the audio (Refer to Radio and CD Player).
YES [Set to the A/C.] : Troubleshoot the A/C Heating and Air Conditioning).
NO [The diagnostic trouble code is not set.] : Go to Step 4.
STEP 4. Check by scan tool MB991958 "Special Function"
Using scan tool MB991958, select "Test" from the special function of the combination meter. Execute the following item to check the tone alarm.
- Item 3: Buzzer(AUTO)
Q. Is the check result normal?
YES Go to Step 5.
NO Replace the combination meter.
STEP 5. Retest the system
Check that the tone alarm normally.
Q. Is the check result normal?
YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
NO Replace the combination meter.