Inspection Procedure 4

Inspection Procedure 4: Keyless operation warning display does not disappear.

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

TROUBLESHOOTING HINTS

- Malfunction of CAN bus line
- Malfunction of combination meter
- Damaged wiring harness and connectors
- Malfunction of the KOS-ECU

DIAGNOSIS

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

Check the DTC B2415 is set to the KOS-ECU.

(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool MB991958.

Connect scan tool MB991958. Refer to "How to connect scan too (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."

(2)Turn the power supply mode of the engine switch to ON.

(3)Check if DTC is set.

(4)Turn the power supply mode of the engine switch to OFF.

Q. Is the DTC B2415 is set?

YES Refer to diagnostic trouble code chart Combination Meter.
NO Go to Step 2.
STEP 2. Using scan tool MB991958, read the combination meter diagnostic trouble code.

Check if DTC is set in the combination meter.

(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool MB991958.

Connect scan tool MB991958. Refer to "How to connect scan too (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."

(2)Turn the power supply mode of the engine switch to ON.

(3)Check if DTC is set.

(4)Turn the power supply mode of the engine switch to OFF.

Q. Is the DTC is set?

YES Troubleshoot the combination meter. Combination Meter.)
NO Go to Step 3.
STEP 3. Using scan tool MB991958, read the diagnostic trouble code.

Check the DTC is set to the KOS-ECU.

(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool MB991958.

Connect scan tool MB991958. Refer to "How to connect scan too (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."

(2)Turn the power supply mode of the engine switch to ON.

(3)Check if DTC is set.

(4)Turn the power supply mode of the engine switch to OFF.

Q. Is the DTC is set?

YES Refer to diagnostic trouble code chart Keyless Operation System (KOS).
NO Go to Step 4.
STEP 4. Check of the troubles.

Check that the keyless operation warning display turns OFF unless the flashing or illumination conditions are met.

Q. Does the warning display operate properly?

YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
NO Replace KOS-ECU and register the ID codes. (Refer to ID Codes Registration Procedure.)