Mitsubishi L200. Manual - part 763

HANDS FREE-ECU

CHASSIS ELECTRICAL

54A-419

Inspection Procedure 4: When the speech switch is pressed, the voice information is not output.

CAUTION

Before replacing the hands free ECU, ensure that the power supply circuit, the earth circuit and the 
communication circuit are normal.

Steering Wheel Voice Control Switch Circuit

CLOCK 
SPRING

STEERING 
WHEEL 
AUDIO 
REMOTE 
CONTROL 
SWITCH

STEERING 
WHEEL 
VOICE 
CONTROL 
SWITCH

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     SI : Silver

RADIO AND CD PLAYER 
OR 
MULTIVISION DISPLAY

VEHICLES WITH MMCS

:

VEHICLES WITH RADIO AND CD PLAYER

:

NOTE

HANDS FREE-ECU

CHASSIS ELECTRICAL

54A-420

COMMENTS ON TROUBLE SYMPTOM
If the voice information is not output when the 
speech switch is pushed, the communication 
between the radio and CD player <vehicles with 
radio and CD player> or multivision display <vehicles 
with MMCS> and the hands free ECU, or the com-
munication between the radio and CD player and the 
steering wheel voice control switch, the hands free 
ECU, or the steering wheel voice control switch may 
have a problem.

PROBABLE CAUSES

• The hands free ECU may be defective.

• The radio and CD player may be defective. 

<vehicles with radio and CD player>

• The multivision display may be defective. <vehi-

cles with MMCS>

• The steering wheel audio remote control switch 

may be defective.

• The steering wheel voice control switch may be 

defective.

• Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Check the diagnosis mode
Check if the hands free ECU can be switched to the 
diagnosis mode. (Refer to 

P.54A-403

 <Using radio 

and CD player> or 

P.54A-406

 <Using multivision dis-

play>.)

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Perform Inspection Procedure 5 
"DIAGNOSIS MODE cannot be made an 
entry." (Refer to 

P.54A-421

.)

STEP 2. Operation check of the steering wheel 
audio remote control switch
Check that the radio and CD player <vehicles with 
radio and CD player> or multivision display <vehicles 
with MMCS> can be operated by the steering wheel 
audio remote control switch.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Troubleshoot the steering wheel audio 
remote control switch. Refer to 

P.54A-383

.

STEP 3. Check the steering wheel voice control 
switch.
Check the continuity of the steering wheel voice con-
trol switch.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Replace the steering wheel voice control 
switch.

STEP 4. Check the steering wheel audio remote 
control switch.
Check the continuity of the steering wheel audio 
remote control switch. (Refer to steering wheel audio 
remote control switch inspection.)

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Replace the steering wheel audio remote 
control switch.

STEP 5. Check the harness wire between C-311 
steering wheel audio remote control switch 
connector terminal No. 3 and C-312 steering 
wheel voice control switch connector terminal 
No.3.

• Check the communication lines for open circuit 

and short circuit.

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Repair the wiring harness.

STEP 6. Connector check: C-310 clock spring 
connector.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Repair the defective connector.

STEP 7. Check the harness wire between C-310 
clock spring connector terminal No. 4 and C-312 
steering wheel voice control switch connector 
terminal No.2.

• Check the communication lines for open circuit 

and short circuit.

Q: Is the check result normal?

YES : 

Go to Step 8.

NO : 

Repair the wiring harness.

STEP 8. Temporarily replace the steering wheel 
voice control switch, and check the trouble 
symptom.

Q: Is the check result normal?

YES : 

Replace the steering wheel voice control 

switch.

NO : 

Replace the radio and CD player <vehicles 
with radio and CD player> or multivision 
display <vehicles with MMCS>.

HANDS FREE-ECU

CHASSIS ELECTRICAL

54A-421

Inspection Procedure 5: DIAGNOSIS MODE cannot be made an entry.

CAUTION

Before replacing the hands free ECU, ensure that the power supply circuit, the earth circuit and the 
communication circuit are normal.

COMMENTS ON TROUBLE SYMPTOM
If the diagnosis mode cannot be made an entry, the 
hands free ECU, the communication between the 
hands free ECU, and the radio and CD player <vehi-
cles with radio and CD player> or multivision display 
<vehicles with MMCS>, or the power supply system 
of the hands free ECU may have a problem.

PROBABLE CAUSES

• The hands free ECU may be defective.

• The radio and CD player may be defective. 

<vehicles with radio and CD player>

• The multivision display may be defective. <vehi-

cles with MMCS>

• Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Check the radio and CD player <vehicles 
with radio and CD player> or multivision display 
<vehicles with MMCS> operation.
Check if the radio and CD player <vehicles with radio 
and CD player> or multivision display <vehicles with 
MMCS> work normally and the sound is output.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Troubleshoot the radio and CD player 

P.54A-232

 <vehicles with radio and CD 

player> or multivision display 

P.54A-314

 

<vehicles with MMCS>.

STEP 2. Connector check: C-173 hands free ECU 
connector, C-126 radio and CD player connector 
<vehicles with radio and CD player>, C-168 
multivision display connector <vehicles with 
MMCS>

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Repair the defective connector.

STEP 3. Check the wiring harness between C-173 
hands free ECU connector terminal No.2, 16 and 
C-126 radio and CD player connector terminal 
No.29, 40 <vehicles with radio and CD player> or 
C-168 multivision display connector terminal 
No.73, 74 <vehicles with MMCS>.

• Check the signal lines for open circuit and short 

circuit.

Q: Is the check result normal?

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     SI : Silver

Hands-Free ECU Communication Circuit

HANDS-FREE ECU

RADIO AND CD PLAYER 
OR 
MULTIVISION DISPLAY

VEHICLES WITH MMCS

:

VEHICLES WITH RADIO AND CD PLAYER

:

NOTE

HANDS FREE-ECU

CHASSIS ELECTRICAL

54A-422

YES : 

Go to Step 4.

NO : 

Repair the wiring harness.

STEP 4. Check if the power supply circuit of 
hands free ECU have a problem.
Perform the Inspection procedure 1 "Check the 
hands free ECU power supply circuit." of the trouble-
shooting. (Refer to 

P.54A-411

.)

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Repair according to the troubleshooting for 
reference.

STEP 5. Replace the hands free ECU temporarily, 
and check the trouble symptom.

Q: Is the check result normal?

YES : 

Replace the hands free ECU.

NO : 

Replace the radio and CD player <vehicles 
with radio and CD player> or multivision 
display <vehicles with MMCS>.

Inspection Procedure 6: Steering wheel voice control switch illumination does not come on.

CAUTION

Before replacing the hands free ECU, ensure that 
the power supply circuit, the earth circuit and the 
communication circuit are normal.

TECHNICAL DESCRIPTION (COMMENT)
The power supply circuit to the steering wheel voice 

control switch, the steering wheel voice control 
switch, or the clock spring may be defective.

TAIL LAMP
RELAY

ETACS-ESU

CLOCK 
SPRING

Steering Wheel Voice Control Switch Illumination Circuit

STEERING 
WHEEL 
VOICE 
CONTROL 
SWITCH

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     SI : Silver