Lexus ES300 (1997 year). Manual — part 139

V08553

24

Noise

NOISE PRODUCED BY VIBRATION OR SHOCK WHILE DRIVING

No

Yes

Is speaker properly installed?

Noise is produced from static eletricity accumulating in the vehicle body.

With vehicles stationary lightly tap each system.
Is noise produced?

Install properly.

Each system faulty.

Is speaker properly installed?

No

No

Yes

Yes

BE–162

–

BODY ELECTRICAL

AUDIO SYSTEM

1546

1997 LEXUS ES300 (RM511U)

V08554

25

Noise

NOISE PRODUCED WHEN ENGINE STARTS

No

Yes

Whistling noise which becomes high–pitched when
accelerator strongly depressed, disappears shortly
after engine stops.

Generator noise.

A/C noise.

Fuel gauge noise.

Horn noise.

Ignition noise.

Turn signal noise.

Washer noise.

Engine coolant temp. gauge noise.

Wiper noise.

Whining noise occurs when A/C is operating.

Scratching noise occurs during sudden acceleration, driving on rough

roads or when ignition switch is turned ON.

Clicking sound is heard when horn button is pressed, then re-

leased. Whirring/grating sound is heard when pushed continu-

ously.

Murmuring sound stops when engine stops.

Tick–tack noise occurs in co–ordination with blinking of
flasher.

Noise occurs during window washer operation.

Scratching noise occurs while engine is running,
and continues a while even after engine stops.

Scraping noise in line with wiper beat.

Other type of noise

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

No

No

No

No

No

No

No

No

–

BODY ELECTRICAL

AUDIO SYSTEM

BE–163

1547

1997 LEXUS ES300 (RM511U)

BE062–01

Z19355

Tweeter

Ignition Switch

Power Amplifier

Tweeter

Instrument Panel Junction Block

RADIO No.1 Fuse

RAD No.2 Fuse

Radio Receiver Assembly

Woofer

CD Auto Changer

Front Speaker

Rear Speaker

BE–164

–

BODY ELECTRICAL

AUDIO SYSTEM

1548

1997 LEXUS ES300 (RM511U)

LOCATION

BE063–01

N21369

Wire Harness Side

N21370

Wire Harness Side

Connector ”A”

Connector ”B”

Connector ”C”

–

BODY ELECTRICAL

AUDIO SYSTEM

BE–165

1549

1997 LEXUS ES300 (RM511U)

INSPECTION

1.

INSPECT CD AUTO CHANGER CIRCUIT

Disconnect connectors from CD auto changer and inspect the
connector on the wire harness side.

Tester connection

Condition

Specified condition

8 – Ground

Constant

Continuity

5 – Ground

Constant

Battery positive voltage

12 – Ground

Ignition switch LOCK

No voltage

12 – Ground

Ignition switch ACC or ON

Battery positive voltage

If the circuit is not as specified, inspect the circuits connected
to other parts.
HINT:

Check the wire harness between the radio receiver as-
sembly and the CD auto changer.

Since the signals to and from the MUTE, R

–

, R

+

, L

–

, L

+

,

TX

–

and TX

+

terminals are serial signals, they cannot or-

dinarily be measured with a tester.

2.

INSPECT POWER AMPLIFIER CIRCUIT

Disconnect the connector from power amplifier and inspect the
connector on the wire harness side.

Tester connection

Condition

Specified condition

C7 – Ground

Constant

Continuity

C3 – Ground

Ignition switch LOCK

No voltage

C3 – Ground

Ignition switch ACC or ON

Battery positive voltage

C4 – Ground

Constant

Battery positive voltage

If the circuit is not as specified, inspect the circuits connected
to other parts.