2000 LEXUS GS400 radio antenna

5 RadioANY AM OR FM DOES NOR WORK
FEW PRESET TUNING BANDS
Problem with radio wave signals or location?
Are both AM and FM defective?Radio assembly faulty.
Go to No.16
Is tape player operating normally? Radio assembly faulty.
Is power for the antenna being output from the radio assembly?
Hiss noise from speaker? Temporarily install another speaker. Functions OK?
Radio assembly faulty. Recheck system after repair.Speaker faulty.
Power amplifier faulty.
Recheck system after repair. Poor signals, poor location.
No
Ye s
Ye s No
No
NoYe s
Ye s
Ye s
Ye s
No
No
± BODY ELECTRICALAUDIO SYSTEM
BE±201
2502 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

6RadioPOOR RECEPTION
Is the condition bad in comparison with other vehicles?
Are there any additional installation parts?
(Sun shade film, telephone antenna, etc.)
Check if there is any scratch and breaking of a wire on
the glass antenna and the defogger pattern.
(visual check. tester)
(See page
BE±190)
Is the contact of the plug jack of the radio OK?
Does the condition get better by using the outer
antenna (such as pillar antenna)?
Is the contact of the antenna terminal on the glass
surface and the defogger terminal?
Is the continuity of the antenna cord OK?
Check the grounding of the antenna, antenna cord,
choke coil, and noise filter. (See page BE±190)
Does the condition get better by replacing
the choke coil?
Does the condition get better by replacing the
antenna cord?Take a measure for contact. An electric wave environment is bad.
Does the condition get better if
removing them?
Influence of additional installation parts.
Repair. (See page BE±108)
Check the radio.
Take a measure for contact.
Grounding failure. Replace the antenna cord.
Replace the choke coil.
Replace the antenna cord. Ye s
No
Exchange the glass.Ye s
Ye s
Ye s
Ye s
Ye s
Ye s
Ye s
Ye s No
No
No
NoNo
No
No
No
NG
OK
Ye s BE±202
± BODY ELECTRICALAUDIO SYSTEM
2503 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

26 Noise NOISE OCCURS
No
Ye s
NG
OK Does the noise occur only in the radio?
Does the noise occur in a particular place?
Is there any additional installation part
around the glass imprinted antenna?
(Sun shade film, telephone antenna etc.)
Does the noise occur even pulling out the
antenna cord from the radio?
Does the noise occur even after pulling out the
antenna terminal on the glass surface?
Isn't there any adhesive (Butyl rubber)
stuck on the bases of the antenna
terminal, defogger terminal and bus bar?
Check the grounding of the antenna,
antenna cord, coke coil, and noise filter.
(See page BE±190) Does the noise occur even after pulling out
the defogger terminal?
Does the condition get better by replacing
the antenna cord.
Noise rediates directly to the antenna from the
generation source. Does the condition get better by replacing
the choke coil?
Replace the antenna cord. Replace the choke coil. Interfering noise from the defogger line
and choke coil.
Grounding failure. Failure of glass installation.
Must plane the butyl rubber. Noise mixing into the antenna cable. Check the radio. Influence of the film or the noise radiation
of the additional installation part. Does the noise stop by removing it? An electric environment.Refer to No.27. (It occurs in the cassette and CD.)
Ye s
Ye s
Ye s
Ye s
Ye s
Ye s
Ye s
Ye s No
No
No
No
No
No
No
No
BE±214
± BODY ELECTRICALAUDIO SYSTEM
2515 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

I04189
Wire Harness Side
Connector ºBº
Connector ºDº Connector ºCº Connector ºAº
± BODY ELECTRICALAUDIO SYSTEM
BE±221
2522 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
6. NAKAMICHI made:
INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT
Disconnect the connectors from the radio receiver assembly,
and inspect the connector on the wire harness side.
Tester connectionConditionSpecified condition
D3 ± GroundConstantContinuity
D4 ± GroundConstantBattery positive voltage
D1 ± GroundIgnition switch LOCKNo voltage
D1 ± GroundIgnition switch ACC or ONBattery positive voltage
*: w/ LEXUS navigation system
If the circuit is not as specified, inspect the circuits connected
to other parts.
HINT:
Check the wire harness between radio receiver assembly and
the CD auto changer, between radio receiver assembly and
power amplifier.
7. INSPECT GLASS IMPRINTED ANTENNA
(Use same procedure as for ºINSPECT DEFOGGER WIRESº
on page BE±108.)
8. REPAIR GLASS IMPRINTED ANTENNA
(Use same procedure as for ºREPAIR DEFOGGER WIRESº on
page BE±108.)

BE10Y±02
I01373
Radio Assembly
Antenna Choke Coil
Antenna Cable
USA/CANADA Models BE±222
± BODY ELECTRICALANTENNA
2523 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ANTENNA
LOCATION

I05320
Radio Assembly
Antenna Choke Coil
Antenna Cable
Motor Antenna
TAIWAN Models
± BODY ELECTRICALANTENNA
BE±223
2524 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

BE0N6±04
I05587
2 5
I05580
2 5
Z08688
2 13
45 768 Wire Harness Side
± BODY ELECTRICALANTENNA
BE±225
2526 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. Auto Antenna Models:
INSPECT ANTENNA MOTOR
(a) Connect the positive (+) lead from the battery to terminal
2 and the negative (±) lead to terminal 5.
(b) Check that the motor turns (moves upward).
NOTICE:
These tests must be done quickly (within 3 ± 5 seconds) to
prevent the coil from burning out.
(c) Then, reverse the polarity, check that the motor turns the
opposite way (moves downward).
NOTICE:
These tests must be done quickly (within 3 ± 5 seconds) to
prevent the coil from burning out.
2. Auto Antenna Models:
INSPECT ANTENNA MOTOR CONTROL RELAY CIR-
CUIT
Disconnect the connector from the relay and inspect the con-
nector on wire harness side, as shown in the chart below.
Tester connectionConditionSpecified condition
7 ± GroundConstantContinuity
1 ± GroundIgnition switch ACC or ON,
and radio switch ON and OthersNo voltage
1 ± GroundIgnition switch ACC or ON,
and radio switch ON and AMBattery positive voltage
2 ± GroundIgnition switch ACC or ON,
and radio or tape or CD switch OFFNo voltage
2 ± GroundIgnition switch ACC or ON,
and radio or tape or CD switch ONBattery positive voltage
3 ± GroundConstantBattery positive voltage
4 ± GroundIgnition switch ACC or ON,
and radio switch ON and OthersNo voltage
4 ± Ground
Ignition switch ACC or ON,
and radio switch ON and
AM or FM (87.9 ± 96.0 MHz)
Battery positive voltage
5 ± GroundIgnition switch ACC or ON,
and radio switch OFFNo voltage
5 ± GroundIgnition switch ACC or ON,
and radio switch ONBattery positive voltage

± INTRODUCTIONFOR ALL OF VEHICLES
IN±17
17 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER
CAUTION:
If large amount of unburned gasoline flows into the converter, it may overheat and create a fire haz-
ard. To prevent this, observe the following precautions and explain them to your customer.
(a) Use only unleaded gasoline.
(b) Avoid prolonged idling.
Avoid running the engine at idle speed for more than 20 minutes.
(c) Avoid spark jump test.
(1) Perform spark jump test only when absolutely necessary. Perform this test as rapidly as possible.
(2) While testing, never race the engine.
(d) Avoid prolonged engine compression measurement.
Engine compression tests must be done as rapidly as possible.
(e) Do not run engine when fuel tank is nearly empty.
This may cause the engine to misfire and create an extra load on the converter.
(f) Avoid coasting with ignition turned off.
(g) Do not dispose of used catalyst along with parts contaminated with gasoline or oil.
3. IF VEHICLE IS EQUIPPED WITH MOBILE COMMUNICATION SYSTEM
For vehicles with mobile communication systems such as two±way radios and cellular telephones, observe
the following precautions.
(1) Install the antenna as far as possible away from the ECU and sensors of the vehicle's electronic
system.
(2) Install the antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the ve-
hicle's electronic systems. For details about ECU and sensors locations, refer to the section on
the applicable component.
(3) Avoid winding the antenna feeder together with other wiring as much as possible, and also avoid
running the antenna feeder parallel with other wire harnesses.
(4) Check that the antenna and feeder are correctly adjusted.
(5) Do not install powerful mobile communications system.
4. FOR USING OBD II SCAN TOOL OR LEXUS HAND±HELD TESTER
CAUTION:
Observe the following items for safety reasons:

Before using the OBD II scan tool or LEXUS hand±held tester, the OBD II scan tool's instruction
book or LEXUS hand±held tester's operator manual should be read thoroughly.

Be sure to route all cables securely when driving with the OBD II scan tool or LEXUS hand±held
tester connected to the vehicle. (i.e. Keep cables away from feet, pedals, steering wheel and
shift lever.)

Two persons are required when test driving with the OBD II scan tool or LEXUS hand±held tes-
ter, one person to drive the vehicle and the other person to operate the OBD II scan tool or LEX-
US hand±held tester.