Mitsubishi Lancer Evolution X. Manual - part 22

DIAGNOSIS

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CONTROLLER AREA NETWORK (CAN)

54C-113

TRANSAXLE 
ASSEMBLY

ENGINE CONTROL MODULE

CAN-C Communication Circuit <TC-SST>

ETACS-ECU

INTERFACE 
CIRCUIT

CAN DRIVE 
CIRCUIT

JOINT CONNECTOR 
(CAN2)

JOINT CONNECTOR 
(CAN3)

JOINT CONNECTOR 
(CAN4)

SHIFT LEVER

ASC-ECU

STEERING 
WHEEL SENSOR

AWC-ECU

NOTE

: THE TERMINAL NUMBERS DESCRIBED 

IN THE CIRCUIT DIAGRAM AGREE WITH 
THE NUMBERS MARKED ON THE 
TRANSAXLE ASSEMBLY CONNECTOR AND 
HARNESS SIDE CONNECTOR.

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-114

.

FUNCTION

If the scan tool MB991958 cannot communicate with 
the ECM, this diagnosis result will be set.

.

TROUBLE JUDGMENT CONDITIONS

If a communication flag is not set for the ECM, the 
ETACS-ECU determines that there is a failure.

.

TROUBLESHOOTING HINTS

• Malfunction of the connector [joint connector 

(CAN3) <M/T>, joint connector (CAN4) 
<TC-SST>, ECM connector or intermediate con-
nector <TC-SST> improperly connected]

• Malfunction of the wiring harness [open circuit 

between the ECM connector and the joint con-
nector (CAN3) <M/T> or the joint connector 
(CAN4) <TC-SST>, power supply circuit to the 
ECM]

• Malfunction of the ECM

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set
• MB992006: Extra Fine Probe
• MB992110: Power plant ECU check harness

STEP 1. Check joint connector (CAN3) C-127 <M/T>, joint 
connector (CAN4) A-14 <TC-SST>, ECM connector B-10 
and intermediate connector A-13 <TC-SST> for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.

CAUTION

The strand end of the twisted wire should be within 10 cm 
(4 inches) from the connector. For details refer to 

P.54C-7

.

Q: Are joint connector (CAN3) C-127 <M/T>, joint 

connector (CAN4) A-14 <M/T>, ECM connector B-10 and 
intermediate connector A-13 <TC-SST> in good 
condition?
YES : Go to Step 2.
NO :  Repair the damaged parts.

AC708949AL

Connectors: A-13, A-14

A-14

A-13

AC709137

Connector: B-10

AB

C-10 (GR)

AC708951CC

Connector: C-127

DIAGNOSIS

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CONTROLLER AREA NETWORK (CAN)

54C-115

STEP 2. Check the wiring harness between joint connector 
(CAN3) C-127 <M/T> or joint connector (CAN4) A-14 
<TC-SST> and ECM connector B-10.

CAUTION

Strictly observe the specified wiring harness repair proce-
dure. For details refer to 

P.54C-7

.

(1) Disconnect joint connector (CAN3) C-127 and ECM 

connector B-10, and check the wiring harness.

(2) Check the wiring harness between joint connector (CAN3) 

C-127 (terminal 4) and ECM connector B-10 (terminal 90) 
<M/T>

OK: Continuity exists (2 Ω or less)

(3) Check the wiring harness between joint connector (CAN3) 

C-127 (terminal 15) and ECM connector B-10 (terminal 91) 
<M/T>

OK: Continuity exists (2 Ω or less)

AC709746

AC709746

Harness side: C-127

AB

Harness side: B-10

TEST 
HARNESS

TEST 
HARNESS

AC709746

Harness side: C-127

AC

Harness side: B-10

TEST 
HARNESS

TEST 
HARNESS

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-116

(4) Check the wiring harness between joint connector (CAN4) 

A-14 (terminal 7) and ECM connector B-10 (terminal 90) 
<TC-SST>

OK: Continuity exists (2 Ω or less)

(5) Check the wiring harness between joint connector (CAN4) 

A-14 (terminal 20) and ECM connector B-10 (terminal 91) 
<TC-SST>

OK: Continuity exists (2 Ω or less)

Q: Is the wiring harness between joint connector (CAN3) 

C-127 <M/T> or joint connector (CAN4) A-14 <TC-SST> 
and ECM connector B-10 in good condition?
YES : Check the power supply circuit of the ECM. Refer to 

GROUP 13A, MFI Diagnosis .

NO :  Repair the wiring harness between joint connector 

(CAN3) C-127 <M/T> or joint connector (CAN4) A-14 
<TC-SST> and ECM connector B-10.

AC709746

Harness side: A-14

AD

Harness side: B-10

TEST 
HARNESS

TEST 
HARNESS

AC709746

Harness side: A-14

AE

Harness side: B-10

TEST 
HARNESS

TEST 
HARNESS