audio TOYOTA SUPRA 1997 Service Owner's Guide

Light Failure Sensor Fuel Pump ECURear Wiper Relay
5. COMPONENTS ADJACENT TO THE BODY PANELS Locations of ECUs (Cont'd)
Many ECUs are mounted in this vehicle.
Take the following precautions during body repair to prevent damage to the ECUs.

Before starting electric welding operations, disconnect the negative (-) terminal cable from the battery.
When the negative (-) terminal cable is disconnected from the battery, memory of the clock and audio
systems will be cancelled. So before starting work, make a record of the contents memorized by each
memory system. Then when work is finished, reset the clock and audio systems as before.
When the vehicle has tilt and telescopic steering, power seat and outside rear view mirror, which are all
equipped with memory function, it is not possible to make a record of the memory contents.
So when the operation is finished, it will be necessary to explain this fact to the customer, and request
the customer to adjust the features and reset the memory.

Do not expose the ECUs to ambient temperatures above 80°C (176°F).
NOTICE: if it is possible the ambient temperature may reach 80°C (176°F) or more, remove the ECUs
from the vehicle before starting work.

Be careful not to drop the ECUs and not to apply physical shocks to them.
Various types of component parts are mounted directly on or adjacently to the body panels.
Strictly observe the following precautions to prevent damaging these components and the body panels
during handling.

Before repairing the body panels, remove their components or apply protective covers over the
components.

Before prying components off using screwdriver or a scraper, etc., attach protective tape to the tool
tip or blade to prevent damaging the components an the body paint.

Before removing components from the outer surface of the body, attach protective tape to the body
to ensure no damage to painted areas.
HINT: Apply touch-up paint to any damaged paint surfaces.

Before drilling or cutting sections, make sure that there are no wires, etc. on the reverse side.
INTRODUCTIONIN-9

197
SRS
NOTICE: When inspecting or repairing the SRS, perform the operation in accordance with the following
precautionary instructions and the procedure and precautions in the Repair Manual for the applicable model year.

Malfunction symptoms of the supplemental restraint system are difficult to confirm, so the diagnostic trouble
codes become the most important source of information when troubleshooting.
When troubleshooting the supplemental restraint system, always inspect the diagnostic trouble codes before
disconnecting the battery.

Work must be started after 90 seconds from the time the Ignition SW is set to the LOCKº position and the
negative (-) terminal cable is disconnected from the battery.
(The supplemental restraint system is equipped with a back-up power source so that if work is started within 90
seconds of disconnecting the negative (-) terminal cable of the battery, the SRS may be activated.)
When the negative (-) terminal cable is disconnected from the battery, memory of the clock and audio systems
will be cancelled. So before starting work, make a record of the contents memorized by each memory system.
When work is finished, reset the clock and audio system as before and adjust the clock.
To avoid erasing the memory of each memory system, never use a back-up power supply from outside the
vehicle.

When removing the steering wheel pad or handling a new steering wheel pad, keep the pad upper surface facing
upward. Also, lock the lock lever of the twin lock type connector at the rear of the pad and take care not to
damage the connector.
(Storing the pad with its metallic surface up may lead to a serious accident if the SRS inflates for some reason.)

Always store a removed or new front passenger airbag assembly with the airbag door facing up. Storing the
airbag assembly with the airbag door facing down could cause a serious accident if the airbag inflates.

Store the steering wheel pad where the ambient temperature remains below 93C (200F), without high humidity
and away from electrical noise.

Never use SRS parts from another vehicle. When replacing SRS parts, replace them with new parts.

Never disassemble and repair the steering wheel pad, front passenger airbag assembly, airbag sensor assembly.

Before repairing the body, remove the airbag sensors if during repair shocks are likely to be applied to the
sensors due to vibration of the body or direct tapping with tools or other parts.

Do not reuse a steering wheel pad.
After evaluating whether the airbag sensor assembly is damaged or not, decide whether or not to reuse it.
(See the Repair Manual for the method for evaluating the airbag sensor assembly.)

When troubleshooting the supplemental restraint system, use a high-impedance (Min. 10 kW/V) tester.

The wire harness of the supplemental restraint system is integrated with the cowl wire harness assembly. The
vehicle wiring harness exclusively for the airbag system is distinguished by corrugated yellow tubing, as are the
connectors.

Do not measure the resistance of the airbag squibs.
(It is possible this will deploy the airbag and is very dangerous.)

If the wire harness used in the supplemental restraint system is damaged, replace the whole wire harness
assembly.

INFORMATION LABELS (NOTICES) are attached to the periphery of the SRS components. Follow the
instructions on the notices.

RS06L-02
- SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS-1
1940 Author
: Date
:
1997 SUPRA (RM502U)
SRS AIRBAG
PRECAUTION
NOTICE:

The SUPRA is equipped with SRS, which comprises a driver airbag, front passenger airbag.
Failure to carry out service operations in the correct sequence could cause the SRS to unex-
pectedly deploy during servicing, possibly leading to a serious accident. Further, if a mistake
is made in servicing the SRS, it is possible that the SRS may fail to operate when required. Be-
fore performing servicing (including removal or installation of parts, inspection or replace-
ment), be sure to read the following items carefully, then follow the correct procedures de-
scribed in the repair manual.

Malfunction symptoms of the SRS are difficult to confirm, so the DTCs become the most impor-
tant source of information when troubleshooting. When troubleshooting the SRS, always in-
spect the DTCs before disconnecting the battery.

Even in cases of a minor collision where the SRS does not deploy, the steering wheel pad, front
passenger airbag assembly and airbag sensor assembly should be inspected (See page RS-9
, RS-22 and RS-34).

Never use SRS parts from another vehicle. When replacing parts, replace them with new parts.

Never disassemble and repair the steering wheel pad, front passenger airbag assembly or air-
bag sensor assembly in order to reuse it.

If the steering wheel pad, front passenger airbag assembly or airbag sensor assembly has been
dropped, or if there are cracks, dents or other defects in the case, bracket or connector, replace
them with new ones.

Use a volt/ohmmeter with high impedance (10 kW/V minimum) for troubleshooting the system's
electrical circuits.

Information labels are attached to the periphery of the SRS components. Follow the instruc-
tions on the notices.

After work on the SRS is completed, perform the SRS warning light check (See page DI-557).

If the vehicle is equipped with a mobile communication system, refer to the precaution in the
IN section.
CAUTION:

Work must be started after 90 seconds from when the ignition switch is turned to the ºLOCKº
position and the negative (-) terminal cable is disconnected from the battery.
(The SRS is equipped with a back-up power source so that if work is started within 90 seconds
from disconnecting the negative (-) terminal cable of the battery, the SRS may be deployed.)

When the negative (-) terminal cable is disconnected from the battery, the memory of the clock
and audio system will be canceled. So before starting work, make a record of the contents mem-
orized in the audio memory system. When work is finished, reset the audio systems as they
were before and adjust the clock. To avoid erasing the memory in each memory system, never
use a back- up power supply from outside the vehicle.

Before repairs, remove the airbag sensor if shocks are likely to be applied to the sensor during
repairs.

Do not expose the steering wheel pad, front passenger airbag assembly or airbag sensor as-
sembly directly to hot air or flames.