Mitsubishi Lancer Evolution X. Manual - part 575

DIAGNOSIS <TC-SST>

TSB Revision

TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-257

DTC P1871: APS system (Signal abnormality)

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.

• Whenever the ECU is replaced, ensure that 

the CAN bus lines are normal.

.

DIAGNOSTIC FUNCTION

TC-SST-ECU receives the periodic communication 
data from the engine control module via the CAN bus 
lines, and checks the data for abnormality.

.

DESCRIPTIONS OF MONITOR METHODS

The APS signal from the engine control module is 
determined to be abnormal.

.

MONITOR EXECUTION

• Continuous

.

MONITOR EXECUTION CONDITIONS 
(OTHER MONITOR AND SENSOR)

Other Monitor (There is no temporary DTC stored 

in memory for the item monitored below)

• P0841: Clutch 1 pressure sensor system (Poor 

performance)

• P0842: Clutch 1 pressure sensor system (Output 

low range out)

• P0843: Clutch 1 pressure sensor system (Output 

high range out)

• P0846: Clutch 2 pressure sensor system (Poor 

performance)

• P0847: Clutch 2 pressure sensor system (Output 

low range out)

• P0848: Clutch 2 pressure sensor system (Output 

high range out)

• P185D: Clutch open not possible
• U0001: Bus off
• U0100: Engine time-out error
• P1803: Shift lever system (CAN or LIN time-out 

error)

• P1870: Engine torque signal abnormality
• P1872: Between shift lever and TC-SST system 

(Q-A function abnormality)

Sensor (The sensor below is determined to be 

normal)

• Clutch 1 pressure sensor
• Clutch 2 pressure sensor
• APS
• Shift lever-ECU

.

DIAGNOSIS <TC-SST>

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TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-258

LOGIC FLOW CHARTS (Monitor Sequence)

.

DTC SET CONDITIONS

Check Conditions

• Voltage of battery: 8 V or more.
• Voltage of battery: 16.5 V or less.
• Time after TC-SST-ECU start: 5 seconds or 

more.

JUDGMENT CRITERIA

• APS signal: SNA, or parity/toggle error.

.

OBD-II DRIVE CYCLE PATTERN

Receives the normal value of the APS signal, or the 
parity/toggle are normal.

.

PROBABLE CAUSES

• The CAN bus line is defective.
• APS malfunction
• Malfunction of engine control module
• Malfunction of TC-SST-ECU

AC902558

START

No

Good

Malfunction

END

Yes

Yes

No

Yes

No

Yes

Yes

No

Monitoring condition met

No

Continuous failure
    for 200 msec

Parity bit = error

APS signal 
   = SNA

APS signal

toggle bit = error

APS signal

DIAGNOSIS <TC-SST>

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TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-259

DIAGNOSTIC PROCEDURE

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. Scan tool CAN bus diagnostics
Using the scan tool, diagnose the CAN bus lines.
Q: Is the check result normal?

YES : Go to Step 2.
NO :  Repair the CAN bus lines. (Refer to GROUP 54C − 

Troubleshooting 

P.54C-15

.) After repairing the CAN 

bus line, go to Step 2.

STEP 2. Scan tool diagnostic trouble code.
Check if the diagnostic trouble code is set to the system other 
than TC-SST.
Q: Is the DTC set?

YES : Perform the relevant troubleshooting.
NO :  Go to Step 3.

STEP 3. Scan tool diagnostic trouble code.
After 15 seconds with the engine idle status, check that the 
diagnostic trouble code for engine is set. (Refer to GROUP 13A 
− Troubleshooting 

P.13A-48

.)

Q: Is the DTC set?

YES : Perform the relevant troubleshooting.
NO :  Go to Step 4.

STEP 4. Check whether the DTC is reset.
After 15 seconds with the engine idle status, check that the 
DTC is reset.
Q: Is DTC No.P1871 set?

YES : Replace the mechatronic assembly. (Refer to 

P.22C-421

.)

NO :  Intermittent malfunction. (Refer to GROUP 00 − How 

to Cope with Intermittent Malfunction 

P.00-15

.)

DIAGNOSIS <TC-SST>

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TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-260

DTC P1872: Between shift lever and TC-SST system (Q-A function abnormality)

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.

• Whenever the ECU is replaced, ensure that 

the CAN bus lines are normal.

.

DIAGNOSTIC FUNCTION

TC-SST-ECU checks that the shift lever-ECU is nor-
mal.

.

DESCRIPTIONS OF MONITOR METHODS

The shift lever-ECU is determined to be abnormal.

.

PROBABLE CAUSES

• Malfunction of the shift lever-ECU
• Malfunction of TC-SST-ECU

DIAGNOSTIC PROCEDURE

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. Scan tool CAN bus diagnostics
Using scan tool MB991958, diagnose the CAN bus lines.
Q: Is the check result normal?

YES : Go to Step 2.
NO :  Repair the CAN bus lines. (Refer to GROUP 54C − 

Troubleshooting 

P.54C-15

.) After repairing the CAN 

bus line, go to Step 2.

STEP 2. Scan tool diagnostic trouble code
Check the shift lever diagnostic trouble code. (Refer to 

P.22C-370

.)

Q: Is the DTC set?

YES : Perform the relevant troubleshooting.
NO :  Go to Step 3.

STEP 3. Replace the shift lever assembly, and check if the 
diagnostic trouble code is reset.
(1) Replace the shift lever assembly. (Refer to 

P.22C-404

.)

(2) Check the DTC.
Q: Is DTC No. P1872 set?

YES : Replace the mechatronic assembly. (Refer to 

P.22C-421

.)

NO :  Intermittent malfunction. (Refer to GROUP 00 − How 

to Cope with Intermittent Malfunction 

P.00-15

.)