Mitsubishi Montero (2002-2004). Manual - part 500

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STEP 2. Check that noise appears when the radio switch is 
turned on while the vehicle is stopped and the radio is 
tapped while tuned away from a station.
NOTE: Body static electric from the shock absorber rubber 
bushings used to prevent vibration, tires, etc. occurs because 
of separation from the ground, causing a buzzing noise. Since 
no measures can be taken to discharge the static electricity of 
the vehicle body. Check that there is no noise.
Q: Does noise appear when the radio switch is turned on 

while the vehicle is stopped and the radio is tapped 
while tuned away from a station?
YES : Go to Step 3.
NO :  It may be static electricity noise.

STEP 3. Verify that the radio is correctly grounded. 
The radio is connected to the ground with an assembling 
screw.
Q: Is the radio correctly grounded?

YES : Go to Step 4.
NO :  Tighten the screw securely. Check that there is no 

noise.

STEP 4. Check by replacing radio and CD player.
Q:  Do the other radio and CD player work normally?

YES : Either repair or replace the original radio and CD 

player. Check that there is no noise.

NO :  Either repair or replace the antenna assembly. Check 

that there is no noise.

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INSPECTION PROCEDURE 12: Noise is Present While Moving (FM).

DIAGNOSIS

STEP 1. Check the state of the antenna.

Q:  Is the mast antenna assembled?

YES : 

Go to Step 2.

NO : 

Assemble the mast antenna. Check that 
there is no noise.

STEP 2. Check the radio after adjusting it.

Q:  Readjust the radio. Is the noise eliminated?

YES : 

 Check that there is no noise.

NO : 

Go to Step 3.

STEP 3. Check with several broadcasting 
stations.
NOTE: Multipath noise and fading noise: Because of 
the frequency of FM waves in extremely high, it is 
highly susceptible to effects from geological forma-
tions and buildings. These effects disrupt the broad-
cast signal and obstruct reception in several ways.

.

•

Multipath noise
This describes the echo that occurs when the 
broadcast signal is reflected by a large obstruc-
tion and enters the receiver with a slight time 
delay relative to the direct signal (repetitious 
buzzing).

•

Fading noise
This is a buzzing noise that occurs when the 
broadcast signal is disrupted by obstructing 
objects and the signal strength fluctuates intri-
cately within a narrow range.

Q: Is the problem station or location specific?

YES : 

The effect of an electrical field condition 

(multipath noise, fading noise) could be the 
cause. Check that there is not noise.

NO : 

Go to Step 4.

STEP 4. Check that noise appears when the radio 
switch is turned on while the vehicle is stopped.
NOTE: Body static electric from the shock absorber 
rubber bushings used to prevent vibration, tires, etc. 
occurs because of separation from the ground, caus-
ing a buzzing noise. There is no measures to dis-
charge the static electricity of the vehicle body. 
Check that there is no noise.

Q: Does noise appear when the radio switch is turned 

on while the vehicle is stopped and the radio is 
tapped while tuned away from a station?
YES : 

Go to Step 5.

NO : 

It may be static electricity noise.

STEP 5. Verify that the radio is correctly 
grounded.
The radio is connected to the ground with an assem-
bling screw.

Q: Is the radio correctly grounded?

YES : 

Go to Step 6.

NO : 

Tighten the screw securely. Check that 
there is no noise.

STEP 6. Check by replacing radio and CD player.

Q:  Do the other radio and CD player work normally?

YES : 

Either repair or replace the original radio 

and CD player. Check that there is no noise.

NO : 

Either repair or replace the antenna 
assembly. Check that there is no noise.

INSPECTION PROCEDURE 13: Constant Noise.

DIAGNOSIS

Use the Symptom Chart to diagnose the possible 
cause(s) of the noise. Noise is often created by the 
following factors:

• Traveling conditions of the vehicle

• Terrain of area traveled through

• Surrounding buildings

• Signal conditions

• Time period

If there are still problems with noise, even after per-
forming inspection procedures 7 to 14, obtain infor-
mation on the factors listed above. Determine 
whether the problem occurs on AM or FM, the station 
names, frequencies, etc. and contact the radio man-
ufacturer's service center.

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INSPECTION PROCEDURE 14: No reception (AM).

DIAGNOSIS

STEP 1. Check the state of the antenna.

Q:  Is the mast antenna assembled?

YES : 

Go to Step 2.

NO : 

Assemble the mast antenna. The radio 
should sound normally.

STEP 2. Check to see if inspections are taking 
place is an area exposed to special electric 
fields.

Q:  Are inspections taking place under special electric 

field conditions? (underground garage, inside a 
building, etc.)?
YES : 

Go to Step 3.

NO : 

Go to Step 4.

STEP 3. Relocate and check the radio.
Automatically receive in a good reception area that is 
not exposed to special electric fields.

Q:  Is reception of the strongest radio frequency 

possible within the area?
YES : 

There is no action to be taken.

NO : 

Go to Step 4.

STEP 4. Tune the radio, and then check it.

Q:  Did the sensitivity improve after tuning?

YES : 

There is no action to be taken.

NO : 

Go to Step 5.

STEP 5. Check the connection of the antenna 
plug and radio and CD player.

Q:  Is the antenna plug thoroughly connected to the 

radio and CD player?
YES : 

Go to Step 6.

NO : 

Thoroughly connect the antenna plug and 
the radio and CD player. The radio should 
sound normally.

STEP 6. Check by replacing radio and CD player.

Q:  Do the other radio and CD player work normally?

YES : 

Either repair or replace the original radio 

and CD player. The radio should sound 
normally.

NO : 

Either repair or replace the antenna 
assembly. The radio should sound normally.

INSPECTION PROCEDURE 15: Poor Reception.

DIAGNOSIS

STEP 1. Check the state of the antenna.

Q:  Is the mast antenna assembled?

YES : 

Go to Step 2.

NO : 

Assemble the mast antenna. Check that a 
poor reception is resolved.

STEP 2. Check to see if inspections are taking 
place is an area exposed to special electric 
fields.

Q:  Are inspections taking place under special electric 

field conditions? (underground garage, inside a 
building, etc.)?
YES : 

Go to Step 3.

NO : 

Go to Step 4.

STEP 3. Relocate and check.
Automatically receive in a good reception area that is 
not exposed to special electric fields.

Q:  Is reception of the strongest radio frequency 

possible within the area?
YES : 

Check that a poor reception is resolved.

NO : 

Go to Step 4.

STEP 4. Tune the radio, and then check it.

Q:  Did the sensitivity improve after tuning?

YES : 

Check that a poor reception is resolved.

NO : 

Go to Step 5.

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STEP 5. Check with several broadcasting 
stations.
NOTE: Two types of noise are addressed in this pro-
cedure, multipath and fading noise. The frequency of 
FM waves is extremely high. This makes them sus-
ceptible to effects from geological formations and 
buildings. These effects disrupt the broadcast signal 
and obstruct reception in many ways.

.

•

Multipath noise is the echo that occurs when the 
broadcast signal is reflected by a large obstruc-
tion and enters the receiver with a slight time 
delay relative to the direct signal (repetitious 
buzzing).

•

A fading or buzzing noise may occur when the 
broadcast beam is disrupted by obstructing 
objects and the signal strength fluctuates within a 
narrow range.

Q:  Is the abnormality in reception generated only 

within a certain range?
YES : 

Check that a poor reception is resolved.

NO : 

Go to Step 6.

STEP 6. Check the connection of the antenna 
plug and radio and CD player.

Q:  Is the antenna plug thoroughly connected to the 

radio and CD player?
YES : 

Go to Step 7.

NO : 

Thoroughly connect the antenna plug and 
the radio and CD player. Check that a poor 
reception is resolved.

STEP 7. Check by replacing radio and CD player.

Q:  Do the other radio and CD player work normally?

YES : 

Either repair or replace the original radio 

and CD player. Check that a poor reception 
is resolved.

NO : 

Either repair or replace the antenna 
assembly. Check that a poor reception is 
resolved.

INSPECTION PROCEDURE 16: Distortion on AM and/or FM.

.

DIAGNOSIS

STEP 1. Check the level of distortion.

Q: How much distortion is there?

Occasional distortion : 

Go to Step 2.

Constant distortion : 

Go to Step 3.

STEP 2. Check the location of the distortion.

Q: Is there distortion when the vehicle is near the 

radio station?
YES : 

The antenna is receiving too strong a signal.

NO : 

Go to Step 3.

STEP 3. Check the wires at each speaker.

Q: Are the speaker wires contacting the paper 

speaker cone?
YES : 

Move the speaker wires away from the 

paper speaker cone. The speaker should 
now be free of distortion.

NO : 

Go to Step 4.

STEP 4. Remove the speakers, and check the 
paper cone for foreign material or damage.

Q: Is there foreign material or damage on the paper 

cone of the speaker?
YES : 

Repair or replace the speakers. The 

speaker should now be free of distortion.

NO : 

Go to Step 5.

STEP 5. Check for distortion with the speaker 
installed.

Q: Does a distortion occur?

YES : 

Install the speaker securely. The speaker 

should now be free of distortion.

NO : 

Repair or replace the radio and CD player. 
The speaker should now be free of 
distortion.