Keyless Operation System (KOS)

DTC B2352: Antenna fail

CAUTION:
When replacing the ECU, always check that the communication circuit is normal.









DTC SET CONDITION

If an open circuit or short to ground occurs in the antenna, KOS-ECU sets DTC B2352.

TECHNICAL DESCRIPTION (COMMENT)

When the ignition switch is turned ON with the emergency operation by the inversely-inserted keyless operation key, KOS-ECU sends signals to the receiver antenna module. The receiver antenna transmits random numbers to the keyless operation key when it receives signals from KOS-ECU. If an open circuit or short to ground occurs on the wiring harness between KOS-ECU and receiver antenna at this time, KOS-ECU determines that there is a problem.

TROUBLESHOOTING HINTS

- Malfunction of the receiver antenna module
- Damaged wiring harness and connectors
- Malfunction of KOS-ECU

DIAGNOSIS

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A

STEP 1. Check receiver antenna module connector C-08 and KOS-ECU connector C-05 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is the receiver antenna module connector C-08 and KOS-ECU connector C-05 in good condition?

YES Go to Step 2.
NO Repair the defective connector.
STEP 2. Check the wiring harness between the receiver antenna module connector C-08 (terminal Nos. 2, 1, 8, 12) and the KOS-ECU connector C-05 (terminal Nos. 11, 12, 32, 7) for open circuit.

(1)Disconnect receiver antenna module connector C-08 and KOS-ECU connector C-05, and check the wiring harness.





(2)Check the wiring harness between receiver antenna module connector C-08 (terminal No.2) and KOS-ECU connector C-05 (terminal No.11)
OK: Continuity exists (2ohms or less)






(3)Check the wiring harness between receiver antenna module connector C-08 (terminal No.1) and KOS-ECU connector C-05 (terminal No.12)
OK: Continuity exists (2ohms or less)






(4)Check the wiring harness between receiver antenna module connector C-08 (terminal No.8) and KOS-ECU connector C-05 (terminal No.32)
OK: Continuity exists (2ohms or less)






(5)Check the wiring harness between receiver antenna module connector C-08 (terminal No.12) and KOS-ECU connector C-05 (terminal No.7)
OK: Continuity exists (2ohms or less)

Q. Is the wiring harness between receiver antenna module connector C-08 (terminal Nos. 2, 1, 8, 12) and the KOS-ECU connector C-05 (terminal Nos. 11, 12, 32, 7) in good condition?

YES : Go to Step 3.

NO (receiver antenna module connector C-08 terminal No.2 - KOS-ECU connector C-05 terminal No.11.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 2) and the KOS-ECU connector C-05 (terminal No. 11).

NO (receiver antenna module connector C-08 terminal No.1 - KOS-ECU connector C-05 terminal No.12.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 1) and the KOS-ECU connector C-05 (terminal No. 12).

NO (receiver antenna module connector C-08 terminal No.8 - KOS-ECU connector C-05 terminal No.32.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 8) and the KOS-ECU connector C-05 (terminal No. 32).

NO (receiver antenna module connector C-08 terminal No.12 - KOS-ECU connector C-05 terminal No.7.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 12) and the KOS-ECU connector C-05 (terminal No. 7).

STEP 3. Check the wiring harness between the receiver antenna module connector C-08 (terminal Nos. 2, 1, 8, 12) and the ground for short circuit.

(1)Disconnect receiver antenna module connector C-08, and check the wiring harness.





(2)Check the wiring harness between receiver antenna module connector C-08 (terminal No.2) and ground
OK: No Continuity






(3)Check the wiring harness between receiver antenna module connector C-08 (terminal No.1) and ground
OK: No Continuity






(4)Check the wiring harness between receiver antenna module connector C-08 (terminal No.8) and ground
OK: No Continuity






(5)Check the wiring harness between receiver antenna module connector C-08 (terminal No.12) and ground
OK: No Continuity

Q. Is the wiring harness between receiver antenna module connector C-08 (terminal Nos. 2, 1, 8, 12) and the ground in good condition?

YES : Go to Step 4.

NO (receiver antenna module connector C-08 terminal No.2 - ground.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 2) and the ground.

NO (receiver antenna module connector C-08 terminal No.1 - ground.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 1) and the ground.

NO (receiver antenna module connector C-08 terminal No.8 - ground.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 8) and the ground.

NO (receiver antenna module connector C-08 terminal No.12 - ground.) : Repair the wiring harness between receiver antenna module connector C-08 (terminal No. 12) and the ground.

STEP 4. Replace the receiver antenna module, and check whether the diagnostic trouble code is reset.





(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 too (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes".
(2)Erase the DTC.
(3)Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(4)Check if the DTC is set.

Q. Is the DTC set?

YES Replace KOS-ECU and register the ID codes (Refer to ID registration procedure manual - ID codes registration judgement table).

NO The procedure is complete.