Mitsubishi Colt Ralliart. Manual - part 309

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54D-65

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-40 intermediate 
connector, B-01 joint connector (CAN2) and B-03 
joint connector (CAN1) 

AC313821

Connectors: B-01, B-03, B-40

AE

B-01, B-03

B-40

B-40

B-03

B-01

CAUTION

The strand end of the twist wire should be within 
10 cm from the connector. For details refer to 

P.54D-5

.

When checking the joint connector, ensure that its 
wiring harness side is not damaged.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the defective connector. Replace the 
joint connector as necessary.

STEP 2. Resistance measurement at B-01 joint 
connector (CAN2) and B-40 intermediate 
connector.

CAUTION

A digital multimeter should be used. For details 
refer to 

P.54D-5

.

CAUTION

The test wiring harness should be used. For 
details refer to 

P.54D-5

.

AC313821

Connectors: B-01, B-40

AC

B-01

B-40

B-40

B-01

(1) Disconnect the joint connector (CAN2) and the 

intermediate connector, and measure at the 
wiring harness side.

(2) Turn the ignition switch to the OFF (LOCK) 

position.

CAUTION

When measuring the resistance, disconnect the 
negative battery terminal. For details refer to 

P.54D-5

.

(3) Ensure that the negative battery terminal is 

disconnected.

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Index

Group

TOC

AC313937AV

Harness side: B-01

Harness side: B-40

Test 
harness

Test 
harness

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54D-66

(4) Continuity between B-40 intermediate connector 

terminal No.3 and B-01 joint connector (CAN2) 
terminal No.7

OK: Continuity (2 

Ω or less) 

AC313937AJ

Harness side: B-01

Test 
harness

Harness side: B-40

Test 
harness

(5) Continuity between B-40 intermediate connector 

terminal No.4 and B-01 joint connector (CAN2) 
terminal No.3

OK: Continuity (2 

Ω or less) 

CAUTION

Strictly observe the specified wiring harness 
repair procedure. For details refer to 

P.54D-5

.

Q: Is the check result normal?

YES : 

<All the resistances measure 2 

Ω or less> 

Follow diagnosis item 5, 6, 8, 9, 10, 11 and 
12. Refer to 

P.54D-13

.

NO  : 

<Either or all of the resistances measure 
more than 2 

Ω> Repair the wiring harness 

between joint connector (CAN1) and joint 
connector (CAN2).

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TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54D-67

Diagnostic Item 8: Diagnose when the M.U.T.-III cannot receive the data sent by engine-ECU <M/T> or 
engine-CVT-ECU <CVT>.

CAUTION

When servicing a CAN bus line, earth yourself by touching a metal object such as an unpainted water 
pipe. If you fail to do, a component connected to the CAN bus line may be broken.

ENGINE-ECU <M/T> OR
ENGINE-CVT-ECU <CVT>

COMBINATION
METER

DIAGNOSIS
CONNECTOR

Wire colour code
B : Black     LG : Light green     G : Green     L : Blue     W : White     Y : Yellow     SB : Sky blue
BR : Brown     O : Orange     GR : Grey     R : Red     P : Pink     V : Violet     PU : Purple

FUNCTION

The diagnostic result demonstrates that "Diagnose 
when the M.U.T.-III cannot receive the data sent by 
engine-ECU <M/T> or engine-CVT-ECU <CVT>" 
when the M.U.T.-III checks the periodically sent data 
from each ECU and cannot receive the engine-ECU 
<M/T> or engine-CVT-ECU <CVT> data only.

TROUBLE JUDGEMENT CONDITIONS

M.U.T.-III judges the trouble when the periodically 
sent data from engine-ECU <M/T> or 
engine-CVT-ECU <CVT> cannot be received and 
sent. 

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TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54D-68

PROBABLE CAUSES

• Damaged harness wires and connectors

• Power supply circuit malfunction of the 

engine-A/T-ECU

• Malfunction of the engine-ECU <M/T> or 

engine-CVT-ECU <CVT>

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-01 joint connector 
(CAN2) and A-08 engine-ECU <M/T> or 
engine-CVT-ECU <CVT> connector

AC509191

Connector: A-08

Harness side

AD

A-08 (GR)

AC313820AF

Connector: B-01

CAUTION

The strand end of the twist wire should be within 
10 cm from the connector. For details refer to 

P.54D-5

.

When checking the joint connector, ensure that its 
wiring harness side and its short pins are not dam-
aged.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the defective connector. Replace the 
joint connector as necessary.

STEP 2. Resistance measurement at B-01 joint 
connector (CAN2) and A-08 engine-ECU <M/T> or 
engine-CVT-ECU <CVT> connector.

CAUTION

A digital multimeter should be used. For details 
refer to 

P.54D-5

.

CAUTION

The test wiring harness should be used. For 
details refer to 

P.54D-5

.

AC509191

Connector: A-08

Harness side

AD

A-08 (GR)

AC313820AF

Connector: B-01

(1) Disconnect the joint connector (CAN2) and the 

engine-ECU <M/T> or engine-CVT-ECU <CVT> 
connector, and measure at the wiring harness 
side. 

(2) Turn the ignition switch to the OFF (LOCK) 

position.

CAUTION

When measuring the resistance, disconnect the 
negative battery terminal. For details refer to 

P.54D-5

.

(3) Ensure that the negative battery terminal is 

disconnected.

Main

Index

Group

TOC