Lexus RX300 (MCU15). Manual - part 424

B00738

Bank 1 Sensor 1

Bank 2 Sensor 1

+B

HT

Ohmmeter

+B

HT

Ohmmeter

FI0W1–01

–

ELECTRONIC FUEL INJECTION

AIR–FUEL RATIO (A/F) SENSOR

FI–67

LEXUS RX300   (RM785E)

AIR–FUEL RATIO (A/F) SENSOR

INSPECTION

INSPECT HEATER RESISTANCE OF A/F SENSORS
(a)

Disconnect the A/F sensor connector.

(b)

Using an ohmmeter measure the resistance between ter-
minals +B and HT.
Resistance: 0.8 – 1.4 Ω at 20°C (68°F)

If the resistance is not as specified, replace the sensor.

Torque: 44 N·m (440 kgf·cm, 31 ft·lbf)

(c)

Reconnect the A/F sensor connector.

FI0W2–01

B05024

Passenger’s Seat

Heated Oxygen Sensor
Connector
(Bank 1 Sensor 2)

Connector
for Seat

37 (375,27)

FI–68

–

ELECTRONIC FUEL INJECTION

OXYGEN SENSOR (Bank 1 Sensor 2)

LEXUS RX300   (RM785E)

OXYGEN SENSOR (Bank 1 Sensor 2)

COMPONENTS

FI0W3–01

B05022

Bank 1 Sensor 2

+B

HT

Ohmmeter

–

ELECTRONIC FUEL INJECTION

OXYGEN SENSOR (Bank 1 Sensor 2)

FI–69

LEXUS RX300   (RM785E)

INSPECTION

INSPECT HEATER RESISTANCE OF HEATED OXYGEN
SENSOR (Bank 1 Sensor 2)
(a)

Remove the driver’s seat.

(b)

Take out the floor carpet.

(c)

Disconnect the oxygen sensor connector.

(d)

Using an ohmmeter, measure the resistance between the
terminals +B and HT.
Resistance: 11 – 16 Ω at 20°C (68°F)

If the resistance is not as specified, replace the sensor.

Torque: 44 N·m (440 kgf·cm, 31 ft·lbf)

(e)

Reconnect the oxygen sensor connector.

(f)

Reinstall the floor carpet.

(g)

Reinstall the driver’s seat.

FI0W4–01

B04961

Engine ECU

Engine ECU Connector

No.2 Instrument
Lower Panel

Under Cover

FI–70

–

ELECTRONIC FUEL INJECTION

ENGINE ECU

LEXUS RX300   (RM785E)

ENGINE ECU

COMPONENTS