Lexus SC300 / Lexus SC400. Manual - part 156

B. with CD player type

Wire harness faulty.

Radio receiver assembly faulty.

Is there continuity between the following terminals
with connector connected?

 Radio receiver amplifier A3 – ground

 Radio receiver amplifier A4 – ground

Power amplifier faulty.

Is there continuity between the following terminals
with connector disconnected?

 Radio receiver assembly A11 – ground

Replace fuse.

Wire harness faulty.

Remove foreign object.

Is there a foreign object inside tape player?

Is radio operating normally?

Check if RADIO No.1 and RADIO No.2 fuses are OK

Wire harness faulty.

Radio receiver assembly faulty.

Is there continuity between the following terminals
with connector disconnected?

 Radio receiver assembly A11 – Power amplifier A11

Is there continuity between the following terminals
with connector disconnected?

 Power amplifier B7–ground.

–

BODY ELECTRICAL SYSTEM

AUDIO SYSTEM

BE–235

12

Tape player

CASSETTE TAPE WILL NOT EJECT

A. without CD player type

Is there battery voltage between the following ter-
minals with connector connected?

 Radio receiver amplifier A3 – ground

 Radio receiver amplifier A4 – ground

Replace fuse.

Wire harness faulty.

Wire harness faulty.

Is radio operating normally?

Check if RADIO No.1 and RADIO NO.2 fuses are OK

Is tape player operating normally?

Radio receiver assembly faulty

Is there continuity between the following terminals
with connector disconnected?

 Radio receiver amplifier A7 – ground

Cassette tape is
jammed or radio receiv-
er assembly faulty.

Radio receiver assem-
bly faulty.

BE–236

–

BODY ELECTRICAL SYSTEM

AUDIO SYSTEM

B. with CD player

Is there battery voltage between the following ter-
minals with connector connected?

 Radio receiver amplifier A3 – ground

 Radio receiver amplifier A4 – ground

Replace fuse.

Wire harness faulty.

Is radio operating normally?

Check if RADIO No.1 and RADIO NO.2 fuses are OK

Is tape player operating normally?

Power amplifier faulty.

Is there continuity between the following terminals
with connector disconnected?

 Radio receiver amplifier A11 – ground

Cassette tape is
jammed or radio receiv-
er assembly faulty.

Radio receiver assem-
bly faulty.

Wire harness faulty.

Wire harness faulty.

Radio receiver assembly faulty.

Is there continuity between the following terminals
with connector disconnected?

 Radio receiver amplifier A11 – Power amplifier A11

Is there continuity between the following terminals
with connector disconnected?

 Power amplifier B7 – ground

–

BODY ELECTRICAL SYSTEM

AUDIO SYSTEM

BE–237

13

Tape player

DISPLAY INDICATES, BUT NO SOUND IS 
PRODUCED (EXCEPT WOOFER)

A. without CD player type

Is radio operating normally?

Radio receiver assembly faulty.

Radio receiver assembly faulty.

Is there continuity between the following terminals
with connector disconnected?

 Radio receiver amplifier B1 – Power switch 14

 Radio receiver amplifier B3 – Power switch 11

When the volume switch is turned from minu-
mum to maximum, does resistance between
terminal B1–B3 of radio receiver assembly
change from 0 to 50 k



?

is resistance value approx. 50 k



 between ter-

minals B3–B6 of radio receiver assembly?

Is there continuity between the following terminals
with connector disconnected?

 Radio receiver amplifier B6 – Power switch 13

Power switch faulty.

Wire harness faulty.

Power switch faulty.

Wire harness faulty.

BE–238

–

BODY ELECTRICAL SYSTEM

AUDIO SYSTEM