Mitsubishi Evolution X. Manual - part 559

DIAGNOSIS

TSB Revision

KEYLESS OPERATION SYSTEM (KOS)

42B-143

STEP 2. Diagnostic trouble code recheck after resetting 
CAN bus lines
Q: Is the DTC C1913, C1923, C1933, C1943, C1914, C1924, 

C1934 or C1944 set?
YES : Go to Step 3.
NO :  The procedure is complete.

STEP 3. Check for TPMS transmitter.
Identify the TPMS transmitter which the DTC is set by TPMS 
transmitter check (Refer to 

P.42B-265

).

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. Then 
register the ID codes (Refer to 

P.42B-265

). Then go 

to Step 4.

NO :  Even when no transmitter is checked, register the ID 

codes. (Refer to 

P.42B-265

.) Then go to Step 4.

STEP 4. Diagnostic trouble code recheck after register the 
ID codes
(1) Turn the ignition switch to the "LOCK" (OFF) position.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC C1913, C1923, C1933, C1943, C1914, C1924, 

C1934 or C1944 set?
YES : Replace the KOS-ECU and register the ID codes 

(Refer to 

P.42B-265

). Then start over at Step 1.

NO :  The procedure is complete.

DIAGNOSIS

TSB Revision

KEYLESS OPERATION SYSTEM (KOS)

42B-144

DTC C1912: Tire Inflation pressure Warning 1

 

DTC C1922: Tire Inflation pressure Warning 2

 

DTC C1932: Tire Inflation pressure Warning 3

 

DTC C1942: Tire Inflation pressure Warning 4

CAUTION

If there is any problem in the CAN bus lines, an incorrect 
diagnostic trouble code may be set. Prior to this diagno-
sis, diagnose the CAN bus lines (Refer to GROUP 54C, 
Trouble code diagnosis 

P.54C-14

).

.

DTC SET CONDITION

When the tire pressure included in the signal from the TPMS 
transmitter is less than the specified value, KOS-ECU sets this 
code.

.

TROUBLESHOOTING HINTS

The most likely causes for this DTC to set is:

• Drop of tire pressure

• Loose TPMS transmitter mounting nut

• Flat tire

• TPMS transmitter malfunction

• KOS-ECU malfunction

• CAN-bus line malfunction

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. M.U.T.-III CAN bus diagnostics
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 (Refer to GROUP 54C 

− 

CAN Bus Diagnostics table 

P.54C-240

). On 

completion, go to Step 2.

STEP 2. Diagnostic trouble code recheck after resetting 
CAN bus lines
Q: Is DTC C1912, C1922, C1932 or C1942 set?

YES : Go to Step 3.
NO :  The procedure is complete.

DIAGNOSIS

TSB Revision

KEYLESS OPERATION SYSTEM (KOS)

42B-145

STEP 3. Tire check
Check that there is no abnormality for the items below.

• Flat tire

• Cracked tire

• Air leak from valve

• Loose TPMS transmitter mounting nut (Refer to 

P.42B-285

).

Q: Is the check result normal?

YES : Go to Step 4.
NO :  Replace it. Then go to Step 4.

STEP 4. Diagnostic trouble code check
(1) Turn the ignition switch to the "ON" position, and adjust the 

pressure to the recommended tire pressure. 

(2) Check if the DTC is set.
Q: Is DTC C1912, C1922, C1932 or C1942 set?

YES : Go to Step 5.
NO :  The procedure is complete.

STEP 5. Diagnostic trouble code check
(1) Drive the vehicle for five minutes.

NOTE: Even within 5 minutes, if the TPMS warning light 
goes out, finish the driving and perform the operation (2). 

(2) Check if the DTC is set.
Q: Is DTC C1912, C1922, C1932 or C1942 set?

YES : Go to Step 6.
NO :  The procedure is complete.

STEP 6. Tire pressure check by M.U.T.-III
(1) Perform the transmitter check using the M.U.T.-III (Refer to 

P.42B-265

), and check the tire pressure values of all the 

wheels. 

(2) Check the tire pressure of all the wheels using the tire 

pressure gauge.

(3) Compare the measured value (1) with (2).

OK: 20 kPa (2.9 psi) or less

NOTE: Do not replace the TPMS transmitter which cannot 
be checked.

Q: Is the check result normal?

YES : Replace the KOS-ECU and register the ID codes 

(Refer to 

P.42B-265

). Then go to Step 9.

NO :  Go to Step 7.

DIAGNOSIS

TSB Revision

KEYLESS OPERATION SYSTEM (KOS)

42B-146

STEP 7. Tire pressure check by M.U.T.-III
(1) Perform the transmitter check using the M.U.T.-III (Refer to 

P.42B-265

), and check the tire pressure values of all the 

wheels. 

(2) Check the tire pressure of all the wheels using the tire 

pressure gauge.

(3) Compare the measured value (1) with (2).

OK: 20 kPa (2.9 psi) or less

Q: Is the check result normal?

YES : Replace the KOS-ECU and register the ID codes 

(Refer to 

P.42B-265

). Then go to Step 9.

NO :  Replace the TPMS transmitter and register the ID 

codes (Refer to 

P.42B-12

). Then go to Step 8.

STEP 8. Recheck for diagnostic trouble code.
(1) Turn the ignition switch to the "LOCK" (OFF) position.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC C1912, C1922, C1932 or C1942 set?

YES : Replace the KOS-ECU and register the ID codes 

(Refer to 

P.42B-265

). Then go to Step 9.

NO :  The procedure is complete.

STEP 9. Recheck for diagnostic trouble code.
(1) Turn the ignition switch to the "LOCK" (OFF) position.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC C1912, C1922, C1932 or C1942 set?

YES : Start over at Step 1.
NO :  The procedure is complete.