IN-14
- INTRODUCTIONFOR ALL OF VEHICLES
14 Author: Date:
1997 SUPRA (RM502U)
(f) AIRBAG SENSOR ASSEMBLY
(1) Never reuse the airbag sensor assembly involved
in a collision when the SRS has deployed.
(2) The connectors to the airbag sensor assembly
should be connected or disconnected with the sen-
sor mounted on the floor. If the connectors are con-
nected or disconnected while the airbag sensor as-
sembly is not mounted to the floor, it could cause
undesired ignition of the supplemental restraint sys-
tem.
(3) Work must be started after 90 seconds from the
time the ignition switch is turned to the ºLOCKº posi-
tion and the negative (-) terminal cable is discon-
nected from the battery, even if only loosening the
set bolts of the airbag sensor assembly.
(g) WIRE HARNESS AND CONNECTOR
The SRS wire harness is integrated with the cowl wire har-
ness assembly and floor wire harness assembly. The
wires for the SRS wire harness are encased in a yellow
corrugated tube. All the connectors for the system are
also a standard yellow color. If the SRS wire harness be-
comes disconnected or the connector becomes broken
due to an accident, etc., repair or replace it as shown on
page RS-38.
2. FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER
If large amounts of unburned gasoline flow into the converter, it may overheat and create a fire hazard. 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 and prolonged braking.
(g) Do not dispose of used catalyst along with parts contaminated with gasoline or oil.
3. IF VEHICLE IS EQUIPPED WITH MOBILE COMMUNICATION SYSTEM
(a) For vehicles with mobile communication systems such as two-way radios and cellular telephones, ob-
serve the following precautions.
(b) Install the antenna as far as possible away from the ECU and sensors of the vehicle's electronic sys-
tem.
N08691
AC0RN-01
N08692
AC-82
- AIR CONDITIONINGAIR CONDITIONING AMPLIFIER
2230 Author: Date:
1997 SUPRA (RM502U)
AIR CONDITIONING AMPLIFIER
REMOVAL
1. REMOVE CENTER CLUSTER PANEL
(See page BO-50)
2. REMOVE RADIO WITH AIR CONDITIONING AMPLIFI-
ER
(a) Remove the 4 screws and radio with the air conditioning
amplifier.
(b) Disconnect the connectors.
3. REMOVE AIR CONDITIONING AMPLIFIER FROM RA-
DIO
(a) Remove the 4 screws and the 4 bolts.
(b) Remove the air conditioning amplifier from radio.
BE0DL-01
- BODY ELECTRICALBODY ELECTRICAL SYSTEM
BE-1
1979 Author: Date:
1997 SUPRA (RM502U)
BODY ELECTRICAL SYSTEM
PRECAUTION
Take care to observe the doing precautions when performing inspections or removal and replacement of
body electrical related parts.
1. HEADLIGHT SYSTEM
Halogen bulbs have pressurized gas inside and require special handling. They can burst if scratched or
dropped. Hold a bulb only by its plastic or metal case.
Don't touch the glass part of a bulb with bare hands.
2. SRS (SUPPLEMENTAL RESTRAINT SYSTEM)
The SUPRA is equipped with an SRS (Supplemental Restraint System) such as the driver airbag and front
passenger airbag. Failure to carry out service operation in the correct sequence could cause the SRS to
unexpectedly deploy during servicing, possibly leading to a serious accident. Before servicing (including re-
moval or installation of parts, inspection or replacement), be sure to read the precautionary notices in the
RS section.
3. AUDIO SYSTEM
If the negative (-) terminal cable is disconnected from the battery, the preset AM, FM 1 and FM 2 sta-
tions stored in memory are erased, so be sure to note the stations and reset them after the battery
terminal is reconnected.
If the negative (-) terminal cable is disconnected from the battery, the ºANTI-THEFT SYSTEMº will
operate when the cable is reconnected, but the radio, tape player and CD player will not operate. Be
sure to input the correct ID number so that the radio, tape player and CD player can be operated again.
4. MOBILE COMMUNICATION SYSTEM
If the vehicle is equipped with a mobile communication system, refer to precautions in the IN section.
BE0EM-01
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 FrequencyAmplitude modulationFrequency modulation 30 kHz
300 kHz3 MHz 30 MHz 300 MHz
LF
MFHFVHF
AM FM
BE2818
FM (Stereo)
FM (Monaural)
AM
BE2819
FadingIonosphere BE-72
- BODY ELECTRICALAUDIO SYSTEM
2050 Author: Date:
1997 SUPRA (RM502U)
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 (ºnoiseº)
easily.
3. RECEPTION PROBLEMS
Besides the problem of static, there are also the problems
called ºfadingº, ºmultipathº and ºfade outº. 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
ºfadingº.
BE2820
Multipath
BE2821
Fade Out
N17398
Example :
HeadCapstan
Pinch Roller
- BODY ELECTRICALAUDIO SYSTEM
BE-73
2051 Author: Date:
1997 SUPRA (RM502U)
(b) Multipath
One type of interference caused by the bounce of radio
waves off of obstructions is called ºmultipathº. Multipath
occurs when a signal from the broadcast transmitter an-
tenna bounces off buildings and mountains and interferes
with the signal that is received directly.
(c) Fade Out
Because FM radio waves are of higher frequencies than
AM radio waves, they bounce off buildings, mountains,
and other obstructions. 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
ºfade outº.
4. COMPACT DISC PLAYER
Compact Disc (hereafter called ºCDº) Players use a laser beam
pick-up to read the digital signals recorded on the CD and re-
produce analog signals of the music, etc. There are 4.7 in. (12
cm) and 3.2 in. (8 cm) discs in the CD player.
HINT:
Never attempt to disassemble or oil any part of the player unit.
Do not insert any object other than a disc into the magazine.
NOTICE:
CD players use an invisible laser beam which could cause
hazardous radiation exposure. Be sure to operate the play-
er correctly as instructed.
5. Tape Player/Head Cleaning:
MAINTENANCE
(a) Raise the cassette door with your finger.
Next, using a pencil or similar object, push in the guide.
(b) Using a cleaning pen or cotton applicator soaked in clean-
er, clean the head surface, pinch rollers and capstans.
BE0EN-01
- BODY ELECTRICALAUDIO SYSTEM
BE-75
2053 Author: Date:
1997 SUPRA (RM502U)
TROUBLESHOOTING
NOTICE:
When replacing the internal mechanism (computer part) of the audio system, be careful that no part
of your body or clothing comes in contact with the terminals of the leads from the IC, etc. of the re-
placement part (spare part).
HINT:
This inspection procedure is a simple troubleshooting which should be carried out on the vehicle during sys-
tem operation and was prepared on the assumption of system component troubles (except for the wires and
connectors, etc.).
Always inspect the trouble taking the following items into consideration.
Open or short circuit of the wire harness
Connector or terminal connection fault
For audio systems with anti-theft system, troubleshooting items marked ( * ) indicate that ºTrou-
bleshooting for ANTI-THEFT SYSTEMº should be carried out first.
ProblemNo.
RadioRadio not operating when power switch turned to 'ON'.1
Display indicates when power switch turned to 'ON', but no sound (including
'noise') is produced.2
Noise present, but AM - FM not operating.3
Any speaker does not work.4
Any AM or FM does not work.5
Few preset turning bands.5
Reception poor.6
Sound quality poor.7
Preset memory disappears.8
Tape PlayerCassette tape cannot be inserted.9
Cassette tape inserts, but no power.10
Power coming in, but tape player not operating.11
Any speaker does not work.12
Sound quality poor.13
Tape jammed, malfunction with tape speed or auto-reverse.14
Cassette tape will not eject.15
CD PlayerCD cannot be inserted.16
CD inserted, but no power.17
Power coming in, but CD player not operating.18
Sound jumps.19
Sound quality poor (Volume faint).20
Any speaker does not work.21
CD will not be ejected.22
Power AmplifierNo power coming in.23
Power coming in, but power amplifier not operating.24
Any speaker does not work.25
AntennaAntenna does not fully extend or fully retract.26
Antenna - related.27
NoiseNoise produced by vibration or shock while driving.28
Noise produced when engine starts.29
The term ºAMº includes LW,MW and SW, and the term ºFWº includes UKW.
V08418
Turn ignition Key from LOCK position to ACC position.
Troubleshooting for ANTI-THEFT SYSTEM
Display A:
ID Number is set.Display E:
ANTI-THEFT SYSTEM opera-
tion condition. (ID number input
error 10 times or more.)Display B
ºSEC display disappears after 1
second.Radio switch ON.
Take to designated radio
service station.Display BDisplay D
Refer to each
malfunction item.Normal
operation.
Radio switch ON. Normal operation.
Cancel ID number, refer to each malfunction item.
Ye s
No
OK
NG
ANTI-THEFT SYSTEM operation condition. (ID number input error 9 times or less.)
Input ID number to cancel ANTI-THEFT SYSTEM, and check display.
Display A"B Display B Display E
Display C"A
Radio switch ON.Refer to each
malfunction item.Take to designated
radio service station.ANTI-THEFT SYSTEM not can-
celled. (ID number input error 10
times or less.)
Display D
ANTI-THEFT SYSTEM cancelled.
Check audio system again.Normal operation.
OK
NG
Cancel ID number, refer to each malfunction item.
Liquid Crystal Display (LCD) or VFD for Audio System
Display ºAº Display ºBº Display ºCº
Display ºDº Example:Display ºEº
2 DIN Type
1 DIN TypeBlank
No Illumination
2 DIN Type
1 DIN Type 2 DIN Type
1 DIN Type Error Times2 DIN Type 1 DIN Type
Radio Display
1 DIN Type 2 DIN Type
HINT:
Refer to Owner's Manual for operation details of ANTI-THEFT SYSTEM.
When the ID number has been cancelled, reset the same number after completing the operation, or
inform the customer that it has been cancelled.
BE-76
- BODY ELECTRICALAUDIO SYSTEM
2054 Author: Date:
1997 SUPRA (RM502U)
1 Radio RADIO NOT OPERATING WHEN POWER SWITCH TURNED TO ºONº
+ B wire harness faulty.
GND faulty.
Power amplifier or wire harness faulty.
Power amplifier or wire harness faulty.
GND faulty.
Check if GND (wire harness side) to power amplifier is OK?
Is tape player operating normally?
Check if RAD-No.2 fuse is OK?
Is ACC applied to power amplifier?
Is + B applied to power amplifier?Ye s
NG
No OK No
No
No
No OK
OK
OK Ye s
Ye s
Ye s
Ye sNG
NG
NG Check if RAD-No.1 fuse is OK?
Is + B applied to radio assembly?
Radio assembly faulty.Replace fuse.
ACC wire harness faulty.
Is ACC applied to radio assembly?
Check if GND (wire harness side) to radio assembly is OK?
Radio assembly faulty.
Replace fuse.
- BODY ELECTRICALAUDIO SYSTEM
BE-77
2055 Author: Date:
1997 SUPRA (RM502U)