Lexus ES300 (1997 year). Service manual — part 269
BE05Z–01
N21235
ON
N21375
Wire Harness Side
N21210
BE–140
–
BODY ELECTRICAL
FUEL LID OPENER SYSTEM
1524
1997 LEXUS ES300 (RM511U)
INSPECTION
1.
INSPECT FUEL LID OPENER SWITCH CONTINUITY
(a)
Check that continuity exists between terminals 2 and 3
with the switch ON.
(Switch button pushed)
(b)
Check that no continuity exists between terminals 2 and
3 with the switch OFF.
(Switch button released)
2.
INSPECT FUEL LID OPENER SWITCH CIRCUIT
Disconnect the connector from the switch and inspect the con-
nector on the wire harness side, as shown.
Tester connection
Condition
Specified condition
2 – Ground
Constant
Continuity
3 – Ground
Constant
Battery positive voltage
If the circuit is not specified, inspect power source or wire har-
ness.
3.
INSPECT FUEL LID OPENER SOLENOID OPERATION
Connect the positive (+) lead from the battery to terminal 1 and
the negative (–) lead to terminal 2, and check that the solenoid
operates in the open direction.
If operation is not as specified, replace the solenoid.
N21377
Wire Harness Side
–
BODY ELECTRICAL
FUEL LID OPENER SYSTEM
BE–141
1525
1997 LEXUS ES300 (RM511U)
4.
INSPECT FUEL LID OPENER SOLENOID CIRCUIT
Disconnect the connector from the solenoid and inspect the
connector on the wire harness side, as shown.
Tester connection
Condition
Specified condition
2 – Ground
Constant
Continuity
1 – Ground
Fuel lid opener switch OFF
No voltage
1 – Ground
Fuel lid opener switch ON
Battery positive voltage
If the circuit is not as specified, inspect the circuits connected
to other parts.
The radio wave bands used in radio broadcasting are as follows:
Frequency
Designation
Radio wave
Modulation method
LF: Low frequency MF: Medium Frequency HF: High Frequency VHF: Very High Frequency
Amplitude modulation
Frequency modulation
30 kHz
300 kHz
3 MHz
30 MHz
300 MHz
LF
MF
HF
VHF
AM
FM
BE060–01
BE2818
FM (Stereo)
FM (Monaural)
AM
BE2819
Fading
lonosphere
BE–142
–
BODY ELECTRICAL
AUDIO SYSTEM
1526
1997 LEXUS ES300 (RM511U)
AUDIO SYSTEM
DESCRIPTION
1.
RADIO WAVE BAND
2.
SERVICE AREA
There are great differences in the size of the service area for AM
and FM monaural. Sometimes FM stereo broadcasts cannot be
received even through AM can be received in very clearly.
Not only does FM stereo have the smallest service area, but it
also picks up static and other types of interference (”noise”)
easily.
3.
RECEPTION PROBLEMS
Besides the problem of static, there are also the problems
called ”fading”, ”multipath” and ”fade out”. These problems are
caused not by electrical noise but by the nature of the radio
waves themselves.
(a)
Fading
Besides electrical interference, AM broadcasts are also
susceptible to other types of interference, especially at
night. This is because AM radio waves bounce off the ion-
osphere at night. These radio waves then interfere with
the signals from the same transmitter that reach the ve-
hicle’s antenna directly. This type of interference is called
”fading”.
BE2820
Multipath
BE2821
Fade Out
AM
FM
Noise occurs at a specific place.
Strong possibility of foreign noise.
Noise occurs when listening to
faint broadcasting.
Noise occurs only at night.
Noise occurs while driving and
at a specific place.
There is a case that the same program is broadcasted
from each local station and that may be the case you are
listening different station if the program is the same.
Strong possibility of the beat from a distant broadcasting.
Strong possibility of multipath noise and fading noise
caused by the changes of FM waves.
–
BODY ELECTRICAL
AUDIO SYSTEM
BE–143
1527
1997 LEXUS ES300 (RM511U)
(b)
Multipath
One type of interference caused by the bounce of radio waves
off of obstructions is called ”multipath”. Multipath occurs when
a signal from the broadcast transmitter antenna bounces off
buildings and mountains and interferes with the signal that is re-
ceived directly.
(c)
Fade Out
Because FM radio waves are of higher frequencies than AM ra-
dio waves, they bounce off buildings, mountains, and other ob-
structions. For this reason, FM signals often seem to gradually
disappear or fade away as the vehicle goes behind a building
or other obstruction. This is called ”fade out”.
4.
NOISE PROBLEMS
(a)
Questionnaire for noise:
It is very important for noise troubleshooting to have good
understanding of the claims from the customers, so that
make the best use of following questionnaire and diag-
nose the problem accurately.
HINT:
In the case that the noise occurrence condition does not meet
any of the above questionnaire, check based on the ”Trouble
Phenomenon”.
Refer to above descriptions for multipath and fading.
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