FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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C1940




DTC C1910: Transmitter low battery voltage abnormality 1
DTC C1920: Transmitter low battery voltage abnormality 2
DTC C1930: Transmitter low battery voltage abnormality 3
DTC C1940: Transmitter low battery voltage abnormality 4
DTC C1911: Reception abnormality 1
DTC C1921: Reception abnormality 2
DTC C1931: Reception abnormality 3
DTC C1941: Reception abnormality 4










CAUTION:
If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines CAN Bus Diagnostics Chart).

DTC SET CONDITION

DTC C1910, C1920, C1930, C1940

- When the reception abnormality warning is activated because of the low battery voltage of the TPMS transmitter.

DTC C1911, C1921, C1931, C1941

- When KOS-ECU cannot receive the signals from the TPMS transmitters while driving for about 20 minutes, this code is set.

TROUBLESHOOTING HINTS

The most likely causes for this DTC to set are:

- Low battery that is incorporated into the TPMS transmitter
- Damaged wiring harness and connector
- Registered IDs unmatched
- Malfunction of Receiver antenna assembly
- Malfunction of TPMS transmitter
- Malfunction of KOS-ECU

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


STEP 1. Using scan tool MB991958, diagnose the CAN bus lines.

Use scan tool to diagnose the CAN bus lines.

Q. Is the check result normal?

YES Go to Step 3.
NO Repair the CAN bus lines Controller Area Network (CAN)).
On completion, go to Step 2.
STEP 2. Diagnostic trouble code recheck after resetting CAN bus lines

Q. Is the DTC C1910, C1920, C1930, C1940, C1911, C1921, C1931 or C1941 set?

YES (When DTC C1911, C1921, C1931 and C1941 are set) : Go to Step 3.
YES (When DTC C1911, C1921, C1931 or C1941 is set) : Go to Step 7.
YES (When DTC C1910, C1920, C1930, C1940, C1911, C1921, C1931 and C1941 are set) : Replace all TPMS transmitters, and then register the ID codes (Refer to ID Codes Registration Procedure).
Then go to Step 8.
NO The procedure is complete.
STEP 3. Connector check: C-05 KOS-ECU connector, C-41 intermediate connector, and D-14 receiver antenna assembly connector

Q. Is the check result normal?

YES Go to Step 4.
NO Repair or replace the defective connector, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.
STEP 4. Wiring harness check between C-05 KOS-ECU connector and D-14 receiver antenna assembly connector.

(1)Disconnect C-05 KOS-ECU connector and D-14 receiver antenna assembly connector.

(2)Measure at the harness connector side of the D-14 receiver antenna assembly.





















(3)Measure the resistance between the D-14 receiver antenna assembly terminals.

- Terminal No.1 - body ground.
- Terminal No.3 - body ground.
- Terminal No.5 - body ground.
- Terminal No.8 - body ground.
- Terminal No.12 - body ground.
OK: No continuity

Q. Is the check result normal?

YES Go to Step 5.

NO (terminal No.1 - body ground.) : The wiring harness between D-14 receiver antenna assembly connector terminal No.1 and C-05 KOS-ECU connector terminal No.12 is shorted to ground. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (terminal No.3 - body ground.) : The wiring harness between D-14 receiver antenna assembly connector terminal No.3 and C-05 KOS-ECU connector terminal No.9 is shorted to ground. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (terminal No.5 - body ground.) : The wiring harness between D-14 receiver antenna assembly connector terminal No.5 and C-05 KOS-ECU connector terminal No.13 is shorted to ground. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (terminal No.8 - body ground.) : The wiring harness between D-14 receiver antenna assembly connector terminal No.8 and C-05 KOS-ECU connector terminal No.32 is shorted to ground. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (terminal No.12 - body ground.) : The wiring harness between D-14 receiver antenna assembly connector terminal No.12 and C-05 KOS-ECU connector terminal No.7 is shorted to ground. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

STEP 5. Wiring harness check between C-05 KOS-ECU connector and D-14 receiver antenna assembly connector.

(1)Disconnect C-05 KOS-ECU connector and D-14 receiver antenna assembly connector.

(2)Measure at the harness connector side of C-05 KOS-ECU connector and D-14 receiver antenna assembly connector.





















(3)Measure the resistance between the terminals.

- C-05 KOS-ECU connector terminal No.7 - D-14 receiver antenna assembly connector terminal No.12.
- C-05 KOS-ECU connector terminal No.9 - D-14 receiver antenna assembly connector terminal No.3.
- C-05 KOS-ECU connector terminal No.12 - D-14 receiver antenna assembly connector terminal No.1.
- C-05 KOS-ECU connector terminal No.13 - D-14 receiver antenna assembly connector terminal No.5.
- C-05 KOS-ECU connector terminal No.32 - D-14 receiver antenna assembly connector terminal No.8.
OK: Continuity exists (2 ohms or less)

Q. Is the check result normal?

YES Go to Step 6.

NO (C-05 KOS-ECU connector terminal No.7 - D-14 receiver antenna assembly connector terminal No.12.) : An open circuit is present in the wiring harness between C-05 KOS-ECU connector terminal No. 7 and D-14 receiver antenna assembly connector terminal No. 12. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (C-05 KOS-ECU connector terminal No.9 - D-14 receiver antenna assembly connector terminal No.3.) : An open circuit is present in the wiring harness between C-05 KOS-ECU connector terminal No. 9 and D-14 receiver antenna assembly connector terminal No. 3. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (C-05 KOS-ECU connector terminal No.12 - D-14 receiver antenna assembly connector terminal No.1.) : An open circuit is present in the wiring harness between C-05 KOS-ECU connector terminal No. 12 and D-14 receiver antenna assembly connector terminal No. 1. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (C-05 KOS-ECU connector terminal No.13 - D-14 receiver antenna assembly connector terminal No.5.) : An open circuit is present in the wiring harness between C-05 KOS-ECU connector terminal No. 13 and D-14 receiver antenna assembly connector terminal No. 5. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

NO (C-05 KOS-ECU connector terminal No.32 - D-14 receiver antenna assembly connector terminal No.8.) : An open circuit is present in the wiring harness between C-05 KOS-ECU connector terminal No. 32 and D-14 receiver antenna assembly connector terminal No. 8. Repair the wiring harness, and then register the ID codes (Refer to ID Codes Registration Procedure). Then go to Step 8.

STEP 6. Receiver antenna assembly check

Register the ID codes.

Q. Is the ID registration completed?

YES Go to Step 8.
NO Replace the receiver antenna assembly, then register the ID codes again (Refer to ID Codes Registration Procedure). Then go to Step 8.
STEP 7. Check for TPMS transmitter.

Identify the TPMS transmitter which the DTC is set by TPMS transmitter check (Refer to TPMS Transmitter Check).

NOTE:
The TPMS transmitter which cannot be checked may be faulty or the ID code may not be registered, thus do not replace it, but register the ID code. If the transmitter is faulty, it is replaced in the ID code registration process.

Q. Are there any TPMS transmitters which are identified?

YES Among the checked TPMS transmitters, replace the TPMS transmitters to which the DTC is set, and then register the ID codes (Refer to ID Codes Registration Procedure).
Then go to Step 8.
NO Even when no transmitter is checked, register the ID codes (Refer to ID Codes Registration Procedure).
Then go to Step 8.
STEP 8. Diagnostic trouble code recheck after register the ID codes

(1)Turn the ignition switch to the "ON" position.

(2)Check if the DTC is set.

(3)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the DTC C1910, C1920, C1930, C1940, C1911, C1921, C1931 or C1941 set?

YES Replace the KOS-ECU and register the ID codes (Refer to ID Codes Registration Procedure).
Then start over at Step 1.
NO The procedure is complete.