Mitsubishi Lancer Evolution X. Manual - part 574

DIAGNOSIS <TC-SST>

TSB Revision

TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-253

• P2728: Clutch/shift pressure solenoid 2 system 

(Overcurrent)

• P2729: Clutch/shift pressure solenoid 2 system 

(Short to ground)

• P2730: Clutch/shift pressure solenoid 2 system 

(Short to power supply)

• P2809: Clutch/shift switching solenoid 2, spool 

stuck

• P2812: Clutch/shift switching solenoid 2 system 

(Open circuit)

• P2814: Clutch/shift switching solenoid 2 system 

(Short to ground)

• P2815: Clutch/shift switching solenoid 2 system 

(Short to power supply)

• P181B: Clutch 1 (Pressure low range out)
• P181C: Clutch 1 (Pressure high range out)
• P181E: Clutch 2 (Pressure low range out)
• P181F: Clutch 2 (Pressure high range out)

Sensor (The sensor below is determined to be 

normal)

• Shift select solenoid 1
• Clutch/shift pressure solenoid 2
• Clutch/shift switching solenoid 2

.

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.
• Engine speed: 650 r/min or more.
• Time since above engine condition: 1.5 seconds 

or more.

• FET (Field Effect Transistor) of high side 3: 

Switched off.

JUDGMENT CRITERIA

• FET output: 100 mV or less. (5 seconds)

.

OBD-II DRIVE CYCLE PATTERN

The FET channel output remains 100 mV or more for 
5 seconds.

.

PROBABLE CAUSES

• Malfunction of TC-SST-ECU
• Malfunction of power supply circuit (open circuit)

AC710728

START

No

Good

Malfunction

END

Continuous failure
for 5 sec

No

Yes

Yes

Monitoring condition met

Yes

No

FET* output < 100 mV

*FET : Field Effect Transistor

DIAGNOSIS <TC-SST>

TSB Revision

TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-254

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. Check the TC-SST-ECU power supply circuit
Refer to 

P.22C-341

.

Q: Is the check result normal?

YES : Go to Step 3.
NO :  Repair the TC-SST-ECU power supply circuit. (Refer 

to 

P.22C-341

.) After repairing the power supply 

circuit, go to Step 3.

STEP 3. Check whether the DTC is reset.
After 10 or more seconds have passed with the engine idle sta-
tus, check that the DTC is reset.
Q: Is DTC No. P186F 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

.)

DTC P1870: Engine torque 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 engine torque 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)

DIAGNOSIS <TC-SST>

TSB Revision

TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-255

• 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)

• P1871: APS system (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

.

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.

AC902557

START

No

Good

Malfunction

END

Yes

Yes

No

Yes

No

Yes

Yes

No

Monitoring condition met

No

Continuous failure
    for 200 msec

Engine torque signal  = SNA

Parity bit = error

Engine torque signal

toggle bit = error

Engine torque signal

DIAGNOSIS <TC-SST>

TSB Revision

TWIN CLUTCH- SPORTRONIC SHIFT TRANSMISSION (TC-SST)

22C-256

JUDGMENT CRITERIA

• Engine torque signal: SNA, or parity/toggle error. 

(immediately)

.

OBD-II DRIVE CYCLE PATTERN

Receives the normal value of the engine torque sig-
nal, or the parity/toggle are normal.

.

PROBABLE CAUSES

• The CAN bus line is defective.
• Malfunction of engine control module
• 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 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.P1870 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

.)