Mitsubishi Lancer (4A9 engine). Manual - part 159

RADIO AND CD PLAYER

CHASSIS ELECTRICAL

54A-298

Code No.B2420 Power integrated circuit

CAUTION

• If there is any problem in the CAN bus lines, 

an incorrect diagnosis code may be set. Prior 
to this diagnosis, always diagnose the CAN 
bus lines.

• Before replacing the radio and CD player, be 

sure to check that the power supply circuit, 
earth circuit, and communication circuit are 
normal.

TROUBLE JUDGMENT
If the radio and CD player continuously apply the 
voltage of 2 V or more to the speakers for 1 minute or 
more, it is determined that the offset voltage is 
exceeded, and then the diagnosis code is set.

COMMENTS ON TROUBLE SYMPTOM
The radio and CD player or CAN bus line may have a 
problem.

PROBABLE CAUSES

• Malfunctions of radio and CD player

• Malfunction of CAN bus line wiring harness and 

connector

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the radio and CD player.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

Code No.B2421 Radio tuner

CAUTION

• If there is any problem in the CAN bus lines, 

an incorrect diagnosis code may be set. Prior 
to this diagnosis, always diagnose the CAN 
bus lines.

• Before replacing the radio and CD player, be 

sure to check that the power supply circuit, 
earth circuit, and communication circuit are 
normal.

TROUBLE JUDGMENT
If the communication cannot be established consec-
utively for 10 times between the incorporated tuner of 
radio and CD player and the microcomputer, the 
diagnosis code is set.

COMMENTS ON TROUBLE SYMPTOM
The radio and CD player or CAN bus line may have a 
problem.

PROBABLE CAUSES

• Malfunctions of radio and CD player

• Malfunction of CAN bus line wiring harness and 

connector

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

RADIO AND CD PLAYER

CHASSIS ELECTRICAL

54A-299

Q: Is the diagnosis code set?

YES : 

Replace the radio and CD player.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

Code No.B2423 6-disc CD player error

CAUTION

• If there is any problem in the CAN bus lines, 

an incorrect diagnosis code may be set. Prior 
to this diagnosis, always diagnose the CAN 
bus lines.

• Before replacing the radio and CD player, be 

sure to check that the power supply circuit, 
earth circuit, and communication circuit are 
normal.

TROUBLE JUDGEMENT
During the use of the 6-disc CD changer of radio and 
CD player, if any of the ERROR,  ERROR01, 
ERROR02, ERROR03, ERROR DC or ERROR HOT 
continues for 1 minute, the diagnosis code is set.

COMMENTS ON TROUBLE SYMPTOM
The radio and CD player or CAN bus line may have a 
problem.

PROBABLE CAUSES

• Malfunctions of radio and CD player

• Malfunction of CAN bus line wiring harness and 

connector

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. CD check
Playback a clean and unscratched CD for 1 minute, 
and recheck if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Playback the clean, unscratched CD for 1 minute.
(4) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Go to Step 3.

NO : 

Clean the CD, use a CD without scratches 
and burrs, or remove the CD burrs, and then 
reinsert the CD.

STEP 3. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the radio and CD player.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

RADIO AND CD PLAYER

CHASSIS ELECTRICAL

54A-300

Code No.B2424 CD player error

CAUTION

• If there is any problem in the CAN bus lines, 

an incorrect diagnosis code may be set. Prior 
to this diagnosis, always diagnose the CAN 
bus lines.

• Before replacing the radio and CD player, be 

sure to check that the power supply circuit, 
earth circuit, and communication circuit are 
normal.

TROUBLE JUDGMENT
During the use of the CD player of radio and CD 
player, if any of the ERROR,  ERROR01, ERROR02, 
ERROR03, ERROR DC or ERROR HOT continues 
for 1 minute, the diagnosis code is set.

COMMENTS ON TROUBLE SYMPTOM
The radio and CD player or CAN bus line may have a 
problem.

PROBABLE CAUSES

• Malfunctions of radio and CD player

• Malfunction of CAN bus line wiring harness and 

connector

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. CD check
Playback a clean and unscratched CD for 1 minute, 
and recheck if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Playback the clean, unscratched CD for 1 minute.
(4) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Go to Step 3.

NO : 

Clean the CD, use a CD without scratches 
and burrs, or remove the CD burrs, and then 
reinsert the CD.

STEP 3. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the radio and CD player.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

Code No.B2450 Switch panel communication

CAUTION

• If there is any problem in the CAN bus lines, 

an incorrect diagnosis code may be set. Prior 
to this diagnosis, always diagnose the CAN 
bus lines.

• Before replacing the radio and CD player, be 

sure to check that the power supply circuit, 
earth circuit, and communication circuit are 
normal.

TROUBLE JUDGEMENT
If the radio and CD player cannot establish the com-
munication with centre panel assembly for 1 minute 
or more, the diagnosis code is set.

COMMENTS ON TROUBLE SYMPTOM
The radio and CD player, centre panel assembly, or 
CAN bus line may have a problem.

PROBABLE CAUSES

• Malfunctions of radio and CD player

• Malfunction of centre panel assembly

• Malfunction of CAN bus line wiring harness and 

connector

RADIO AND CD PLAYER

CHASSIS ELECTRICAL

54A-301

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. Connection status check of radio and CD 
player with centre panel assembly
Check that the radio and CD player are connected to 
the centre panel assembly without any problem.

Q: Is the connection established?

YES : 

Go to Step 3.

NO : 

Securely connect the radio and CD player 
with the centre panel assembly.

STEP 3. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the radio and CD player.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

Code No.B2451 Audio panel type error

CAUTION

If there is any problem in the CAN bus lines, an 
incorrect diagnosis code may be set. Prior to this 
diagnosis, always diagnose the CAN bus lines.
TROUBLE JUDGMENT
If the radio and CD player consecutively receive the 
display trouble signal from the centre panel assem-
bly for 1 minute, the diagnosis code is set.

COMMENTS ON TROUBLE SYMPTOM
The centre panel assembly or CAN bus line may 
have a problem.

PROBABLE CAUSES

• Malfunction of centre panel assembly

• Malfunction of radio and CD player

• Malfunction of CAN bus line wiring harness and 

connector

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Go to Step 3.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

STEP 3. Replace the centre panel assembly 
temporarily, and check whether the diagnosis 
code is set.
Check again if the diagnosis code is set to the radio 
and CD player.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the radio and CD player.

NO : 

Replace the centre panel assembly.