sensor LEXUS GS400 2000 Service Repair Manual

SF0O8±01
B07574
Voltmeter
Disconnect
E2VC
B07575
Disconnect
Pressure
Vacuum
PTNK
ECM
E2Voltmeter
± SFI (2JZ±GE)VAPOR PRESSURE SENSOR
SF±61
1527 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT POWER SOURCE VOLTAGE OF VAPOR
PRESSURE SENSOR
(a) Disconnect the vapor pressure sensor connector.
(b) Turn the ignition switch ON.
(c) Using a voltmeter, measure the voltage between connec-
tor terminals VC and E2 of the wiring harness side.
Voltage: 4.5 ± 5.5 V
(d) Turn the ignition switch OFF.
(e) Reconnect the vapor pressure sensor connector.
2. INSPECT POWER OUTPUT OF VAPOR PRESSURE
SENSOR
(a) Turn the ignition switch ON.
(b) Disconnect the vacuum hose from the vapor pressure
sensor.
(c) Connect a voltmeter to terminals PTNK and E2 of the
ECM, and measure the output voltage under these condi-
tions:
(1) Apply vacuum (2.0 kPa (15 mmHg, 0.59 in.Hg)) to
the vapor pressure sensor.
Voltage: 1.3 ± 2.1 V
(2) Release the vacuum from the vapor pressure sen-
sor.
Voltage: 3.0 ± 3.6 V
(3) Apply pressure (1.5 kPa (15 gf/cm
2, 0.22 psi)) to the
vapor pressure sensor.
Voltage: 4.2 ± 4.8 V
(d) Turn the ignition switch OFF.
(e) Reconnect the vacuum hose to the vapor pressure sen-
sor.

SF0O9±04
B08975
N´m (kgf´cm, ft´lbf) : Specified torque

Non±reusable part
Knock Sensor 1
44 (450, 33)
Knock Sensor Connector
44 (450, 33)
Knock Sensor 2
Knock Sensor Connector
Engine Wire Clamp

O±Ring
Oil Dipstick and Guide for A/TPS Pump Rear Stay
Starter
Starter ConnectorClamp Bracket
Starter Wire
Engine Cover
SF±62
± SFI (2JZ±GE)KNOCK SENSOR
1528 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
KNOCK SENSOR
COMPONENTS

SF0OA±04
B09503
SST
P01630
OhmmeterNo Continuity
± SFI (2JZ±GE)KNOCK SENSOR
SF±63
1529 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. REMOVE ENGINE COVER
Remove the 4 nuts and engine cover.
2. REMOVE PS PUMP REAR STAY
3. REMOVE KNOCK SENSOR 1
(a) Disconnect the knock sensor connector.
(b) Using SST, remove the knock sensor.
SST 09816±30010
4. REMOVE OIL DIPSTICK AND GUIDE FOR A/T
(See page EM±62)
5. REMOVE STARTER (See page ST±4)
6. REMOVE KNOCK SENSOR 2 (See step 2)
7. INSPECT KNOCK SENSORS
Using an ohmmeter, check that there is no continuity between
the terminal and body.
If there is continuity, replace the sensor.
8. REINSTALL KNOCK SENSORS
(a) Using SST, install the knock sensor.
SST 09816±30010
Torque: 44 N´m (450 kgf´cm, 33 ft´lbf)
(b) Connect the knock sensor connector.
9. REINSTALL STARTER (See page ST±16)
10. REINSTALL OIL DIPSTICK AND GUIDE FOR A/T
HINT:
Use a new O±ring.
11. REINSTALL PS PUMP REAR STAY
Torque: 39.2 N´m (400 kgf´cm, 29 ft´lbf)
12. REINSTALL ENGINE COVER
Reinstall the engine cover with the 4 nuts.

SF0OB±03
B08325
Bank 1 Sensor 1
N´m (kgf´cm, ft´lbf): Specified torque
Heated Oxygen Sensor Connector
(On Water Pump)
Clamp
45 (450, 33)Heated Oxygen Sensor
B08326
Bank 1 Sensor 2
N´m (kgf´cm, ft´lbf) : Specified torque
Heated Oxygen Sensor Connector
Case Clamp
Front Suspension Member Brace
45 (450, 33)Heated Oxygen Sensor
SF±64
± SFI (2JZ±GE)HEATED OXYGEN SENSOR
1530 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
HEATED OXYGEN SENSOR
COMPONENTS

B08327
Bank 2 Sensor 1
N´m (kgf´cm, ft´lbf) : Specified torquePCV Hose
PS Air Hose
Air Cleaner Inlet
Wire Grommet EVAP Hose
Heated Oxygen Sensor
(Bank 2 Sensor 1)

Gasket Air Cleaner,
MAF Meter and
Intake Air Resonator
Assembly
MAF Meter Connector
Front Exhaust
Pipe

Gasket Engine Wire Clamp
Heated Oxygen Sensor
Connector
Case Clamp

Clamp
Pipe Support Bracket
Heated Oxygen Sensor Connector

Non±reusable part
44 (440, 32)
40 (408, 30)
44 (440, 32)
Exhaust Manifold
x 8
Engine Cover
± SFI (2JZ±GE)HEATED OXYGEN SENSOR
SF±65
1531 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

B02815
Heated Oxygen Sensor Connector
Under CoverFloor Carpet
Wire Grommet
Heated Oxygen Sensor
45 (450, 33)
N´m (kgf´cm, ft´lbf): Specified torque Bank 2 Sensor 2 SF±66
± SFI (2JZ±GE)HEATED OXYGEN SENSOR
1532 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

SF0OC±04
B08610
Ohmmeter
+B
HT
B02065
+B
HTOhmmeter
± SFI (2JZ±GE)HEATED OXYGEN SENSOR
SF±67
1533 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT HEATER RESISTANCE OF HEATED
OXYGEN SENSORS (BANK 1, 2 SENSOR 1 AND
BANK 1 SENSOR 2)
(a) Disconnect the oxygen sensor connectors.
(b) Using an ohmmeter, measure the resistance between the
terminals +B and HT.
Resistance: 11 ± 16 W at 20°C (68°F)
If the resistance is not as specified, replace the sensor.
Torque: 45 N´m (450 kgf´cm, 33 ft´lbf)
(c) Reconnect the oxygen sensor connectors.
2. INSPECT HEATER RESISTANCE OF HEATED
OXYGEN SENSOR (BANK 2 SENSOR 2)
(a) Take out the front side of the floor carpet.
(b) Disconnect the oxygen sensor connector.
Using an ohmmeter, measure the resistance between the
terminals +B and HT.
Resistance: 11 ± 16 W at 20°C (68°F)
If the resistance is not as specified, replace the sensor.
Torque: 45 N´m (450 kgf´cm, 33 ft´lbf)
(c) Reconnect the oxygen sensor connector.
(d) Reinstall the floor carpet.
3. INSPECT OPERATION OF HEATED OXYGEN SEN-
SOR (See page DI±44)

RS01Y±06
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±1
2232 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
SRS AIRBAG
PRECAUTION
NOTICE:

The LEXUS GS 400/300 is equipped with SRS, which comprises a driver airbag, front passenger
airbag and side airbag. Failure to carry out service operations in the correct sequence could
cause the SRS to unexpectedly 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. Before performing servicing (including removal or installation of parts, inspec-
tion or replacement), be sure to read the following items carefully, then follow the correct proce-
dures described 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, side airbag assembly, airbag sensor assembly, front airbag sen-
sor and side airbag sensor assembly should be inspected (See page RS±15, RS±29, RS±42
, RS±60 and RS±65).

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, side
airbag assembly, airbag sensor assembly, front airbag sensor or side airbag sensor assembly
in order to reuse it.

If the steering wheel pad, front passenger airbag assembly, side airbag assembly, airbag sen-
sor assembly, front airbag sensor or side 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 or SRS side airbag
warning light check (See page DI±552).

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, side airbag assembly,
airbag sensor assembly, front airbag sensor or side airbag sensor assembly directly to hot air
or flames.

RS01Z±02
H02570
H02571Spiral Cable
H02572
H02573
H03446
RS±2
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
2233 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
OPERATION
1. STEERING WHEEL PAD (with AIRBAG)
The inflater and bag of the SRS are stored in the steering wheel
pad and cannot be disassembled. The inflater contains a squib,
igniter charge, gas generant, etc., and inflates the bag when
instructed by the airbag sensor assembly.
2. SPIRAL CABLE (in COMBINATION SWITCH)
A spiral cable is used as an electrical joint from the vehicle body
side to the steering wheel.
3. FRONT PASSENGER AIRBAG ASSEMBLY
The inflater and bag of the SRS are stored in the front passen-
ger airbag assembly and cannot be disassembled. The inflater
contains a squib, igniter charge, gas generant, etc., and inflates
the bag when instructed by the airbag sensor assembly.
4. SIDE AIRBAG ASSEMBLY
The inflater and bag of the SRS side airbag are stored in the
side airbag assembly and cannot be disassembled. The inflater
contains a squib, igniter charge, gas generant, etc., and inflates
the bag when instructed by the side airbag sensor assembly.
5. SEAT BELT PRETENSIONER
The seat belt pretensioner system is a component of the front
seat outer belt. The pretensioner contains a squib, gas gener-
ant, wire, piston, etc., and operates in the event of a frontal colli-
sion.

H02575
H02574
H02700
H02576
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±3
2234 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
6. SRS WARNING LIGHT
The SRS warning light is located on the combination meter. It
goes on to alert the driver of trouble in the system when a mal-
function is detected in the airbag sensor assembly. In normal
operation conditions when the ignition switch is turned to the
ACC or ON position, the light goes on for apporx. 6 seconds and
then goes off.
7. AIRBAG SENSOR ASSEMBLY
The airbag sensor assembly is mounted on the floor inside the
lower center finish panel. The airbag sensor assembly consists
of an airbag sensor, safing sensor, diagnosis circuit, ignition
control and drive circuit, etc. It receives signals from the airbag
sensor and judges whether the SRS must be activated or not.
8. FRONT AIRBAG SENSOR
The front airbag sensor is mounted inside each of the front
members. The sensor unit is a mechanical type. When the sen-
sor detects deceleration force above a predetermined limit,
contact is made in the sensor, sending a signal to the airbag
sensor assembly. The sensor cannot be disassembled.
9. SIDE AIRBAG SENSOR ASSEMBLY
The side airbag sensor assembly is mounted in the LH and RH
center pillar. The side airbag sensor assembly consists of a side
airbag sensor, safing sensor, diagnosis circuit, ignition control
and drive circuit, etc. It receives signals from the side airbag
sensors and judges whether the SRS side airbag must be acti-
vated or not.