Mitsubishi Montero Sport (2004+). Manual — part 560

RADIO AND TAPE PLAYER

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CHASSIS ELECTRICAL

54-227

INSPECTION PROCEDURE 10: Some Noise Appears when there is Vibration or Shocks during
Traveling.

.

DIAGNOSIS

STEP 1. Check that the connectors are properly
connected.
NOTE: For the corresponding connectors, etc., refer
to GROUP 90, Radio and Tape Player <vehicles
without amplifier.> or <vehicles with amplifier.>

Q: Are the connectors properly connected?

YES :

Go to Step 2.

NO :

Check the condition of the connector. Refer
to GROUP 00E, Harness Connector
Inspection

P.00E-2

. Check that there is no

noise.

STEP 2. Check that noise appears when the radio
switch is turned on while the vehicle is stopped.
NOTE: Static electricity noise: Body static electric
from the shock absorber rubber bushings used to
prevent vibration, tires, etc. occurs because of sepa-
ration 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. Check that the radio is correctly
grounded.

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 that the antenna is correctly
grounded. (If noise appears when the antenna is
moved, this means the ground is not securely
connected.)

Q: Is the antenna correctly grounded?

YES :

Repair or replace the radio. Check that

there is no noise.

NO :

If rust is present on the antenna ground
screw, clean off the rust and tighten the
ground screw securely. Check that there is
no noise.

INSPECTION PROCEDURE 11: Noise Sometimes Appears on FM during Traveling.

.

Radio and CD Player Circuit
Refer to GROUP 90, Radio and Tape Player <vehi-
cles without amplifier> or <vehicles with amplifier>.

.

DIAGNOSIS

STEP 1. Retune the radio, and check that there is
no noise.

Q: Does the problem clear up when returned?

YES :

Check that there is no noise.

NO :

Go to Step 2.

STEP 2. Check that the noise appears only in
certain locations and only with certain 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 beam is disrupted by obstructing
objects and the signal strength fluctuates intri-
cately within a narrow range.

RADIO AND TAPE PLAYER

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CHASSIS ELECTRICAL

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Q: Does the problem appear only in certain locations

and only with certain stations?

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 3.

STEP 3. Check that the connectors are properly
connected.
NOTE: For the corresponding connectors, etc., refer
to GROUP 90, Radio and Tape Player <vehicles
without amplifier.> or <vehicles with amplifier.>.

Q: Are the connectors properly connected?

YES :

Go to Step 4.

NO :

Check the condition of the connector. Refer
to GROUP 00E, Harness Connector
Inspection

P.00E-2

. Check that there is no

noise.

STEP 4. Check that noise appears when the radio
switch is turned on while the vehicle is stopped.
NOTE: Static electricity noise: Body static electric
from the shock absorber rubber bushings used to
prevent vibration, tires, etc. occurs because of sepa-
ration from the ground, causing a buzzing noise.
There is no measures to discharge the static electric-
ity 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. Check that the radio is correctly
grounded.

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 that the antenna is correctly
grounded. (If noise appears when the antenna is
moved, this means the ground is not securely
connected.)

Q: Is the antenna correctly grounded?

YES :

Repair or replace the radio. Check that

there is no noise.

NO :

If rust is present on the antenna ground
screw, clean off the rust and tighten the
ground screw securely. Check that there is
no noise.

INSPECTION PROCEDURE 12: Ever-present Noise.

.

Diagnosis
Noise is often created by the following factors, and often the
radio is OK when it is checked individually.

• Traveling conditions of the vehicle

• Terrain of area traveled through

• Surrounding buildings

• Signal conditions

• Time period

For this reason, if there are still problems with noise even after
the measures described in inspection procedure 7 to 14 have
been taken, get information on the factors listed above as well
as determining whether the problem occurs with AM or FM, the
station names, frequencies, etc. and contact the radio manu-
facturer's service center.

RADIO AND TAPE PLAYER

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CHASSIS ELECTRICAL

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INSPECTION PROCEDURE 13: There is Noise but No Reception for Both AM and FM or No Sound
from AM, or No Sound from FM.

.

DIAGNOSIS

STEP 1. Make sure that the check is being
conducted under special electrical field
conditions.

Example: In an underground garage or inside a
building.

Q: Is the check being conducted under special

electrical field conditions?

YES :

Go to Step 2.

NO :

Go to Step 3.

STEP 2. Check that proper performance is
obtained when the vehicle is moved.

Q: Is proper performance obtained when the vehicle is

moved?

YES :

The radio should sound normally.

NO :

Go to Step 3.

STEP 3. Check that tuning solves the problem.

Q: Does tuning solve the problem?

YES :

The radio should sound normally.

NO :

Go to Step 4.

STEP 4. Check that the antenna plug and radio
unit are properly connected.

Q: Are the antenna plug and radio unit properly

connected?

YES :

Go to Step 5.

NO :

Reconnect the antenna plug and radio unit
properly. The radio should sound normally.

STEP 5. Check that the problem disappear if
another radio is used.

Q: Does the problem disappear if another radio is

used?

YES :

Repair or replace the radio. The radio

should sound normally.

NO :

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

INSPECTION PROCEDURE 14: Poor Reception.

.

DIAGNOSIS

STEP 1. Make sure that the check is being
conducted under special electrical field
conditions.

Q: Is the check being conducted under special

electrical field conditions (such as in an
underground garage or inside a building)?

YES :

Go to Step 2.

NO :

Go to Step 3.

STEP 2. Check that proper performance is
obtained when the vehicle is moved.

Q: Is proper performance obtained when the vehicle

is moved?

YES :

Check that a poor reception is resolved.

NO :

Go to Step 3.

STEP 3. Check that tuning solves the problem.

Q: Does tuning solve the problem?

YES :

Check that a poor reception is resolved.

NO :

Go to Step 4.

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STEP 4. Check that the problem is limited to the
reception of a specific radio station from a
specific position.
NOTE: Multipath noise and fading noise: Because
the frequency of FM waves is 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 beam is disrupted by obstructing
objects and the signal strength fluctuates intri-
cately within a narrow range.

Q: Is the problem limited to the reception of a specific

radio station from a specific position?

YES :

Go to Step 5.

NO :

Check that a poor reception is resolved.

STEP 5. Check that the antenna plug is
connected to the radio properly.

Q: Is the antenna plug connected to the radio

properly?

YES :

Go to Step 6.

NO :

Reconnect the antenna plug and radio unit
properly. Check that a poor reception is
resolved.

STEP 6. Check that the problem disappears when
another radio is used.

Q: Does the problem disappear if another radio is

used?

YES :

Repair or replace the radio. Check that a

poor reception is resolved.

NO :

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

INSPECTION PROCEDURE 15: Distortion on AM or on Both AM and FM.

.

DIAGNOSIS

STEP 1. Check how much distortion there is.

Q: How much distortion is there?

Occasional distortion :

Go to Step 2.

Constant distortion :

Go to Step 3.

STEP 2. Check that there is distortion near the
radio station.

Q: Is there distortion near the radio station?

YES :

The antenna may receive too strong signal.

NO :

Go to Step 3.

STEP 3. Check that the speaker cords are in
contact with the cone paper.

Q: Are the speaker cords in contact with the cone

paper?

YES :

Move the cords away from the cone paper.

Check that a distortion is resolved.

NO :

Go to Step 4.

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

Q: Is there torn cone paper or foreign material?

YES :

Repair or replace the speakers. Check that

a distortion is resolved.

NO :

Go to Step 5.

STEP 5. Check for distortion with the speaker
installed.

Q: Does a distortion occur?

YES :

Install the speaker securely. Check that a

distortion is resolved.

NO :

Repair or replace the radio. Check that a
distortion is resolved.