Lexus RX300 (MCU15). Service manual - part 421

I06870

EFI Main
Relay

FI0VR–01

S04947

Continuity

Ohmmeter

Ohmmeter

No Continuity

1

2

3

5

S04946

Battery

Ohmmeter

Continuity

1

2

3

5

–

ELECTRONIC FUEL INJECTION

EFI MAIN RELAY

FI–55

LEXUS RX300   (RM785E)

EFI MAIN RELAY

INSPECTION

1.

REMOVE EFI MAIN RELAY (Marking: EFI)

2.

INSPECT EFI MAIN RELAY CONTINUITY

(a)

Using an ohmmeter, check that there is continuity be-
tween terminals 1 and 2.

If there is no continuity, replace the relay.
(b)

Check that there is no continuity between terminals 3 and
5.

If there is continuity, replace the relay.

3.

INSPECT EFI MAIN RELAY OPERATION

(a)

Apply battery voltage across terminals 1 and 2.

(b)

Using an ohmmeter, check that there is continuity be-
tween terminals 3 and 5.

If there is no continuity, replace the relay.
4.

REINSTALL EFI MAIN RELAY

B09976

A/F Sensor 
Heater 
Relay

FI0VS–01

S04947

Continuity

Ohmmeter

Ohmmeter

No Continuity

1

2

3

5

S04946

Battery

Ohmmeter

Continuity

1

2

3

5

FI–56

–

ELECTRONIC FUEL INJECTION

A/F SENSOR HEATER RELAY

LEXUS RX300   (RM785E)

A/F SENSOR HEATER RELAY

INSPECTION

1.

REMOVE RELAY BOX COVER

2.

REMOVE A/F SENSOR HEATER RELAY (Marking: A/F
HTR)

3.

INSPECT A/F SENSOR HEATER RELAY CONTINUITY

(a)

Using an ohmmeter, check that there is continuity be-
tween terminals 1 and 2.

If there is no continuity, replace the relay.
(b)

Check that there is no continuity between terminals 3 and
5.

If there is continuity, replace the relay.

4.

INSPECT A/F SENSOR HEATER RELAY OPERATION

(a)

Apply battery voltage across terminals 1 and 2.

(b)

Using an ohmmeter, check that there is continuity be-
tween terminals 3 and 5.

If there is no continuity, replace the relay.
5.

REINSTALL A/F SENSOR HEATER RELAY

6.

REINSTALL RELAY BOX COVER

I19409

Circuit Opening Relay

FI0VT–01

S04947

Continuity

Ohmmeter

Ohmmeter

No Continuity

1

2

3

5

S04946

Battery

Ohmmeter

Continuity

1

2

3

5

–

ELECTRONIC FUEL INJECTION

CIRCUIT OPENING RELAY

FI–57

LEXUS RX300   (RM785E)

CIRCUIT OPENING RELAY

INSPECTION

1.

REMOVE CIRCUIT OPENING RELAY (Marking: CIR
OPN)

Remove the circuit opening relay from R/B No.1.

2.

INSPECT CIRCUIT OPENING RELAY CONTINUITY

(a)

Using an ohmmeter, check that there is continuity be-
tween terminals 1 and 2.

If there is no continuity, replace the relay.
(b)

Check that there is no continuity between terminals 3 and
5.

If there is continuity, replace the relay.

3.

INSPECT CIRCUIT OPENING RELAY OPERATION

(a)

Apply battery voltage across terminals 1 and 2.

(b)

Using an ohmmeter, check that there is continuity be-
tween terminals 3 and 5.

If there is no continuity, replace the relay.
4.

REINSTALL CIRCUIT OPENING RELAY

FI0VU–01

B04805

V–Bank Cover

EVAP Hose

VSV for EVAP

VSV for EVAP Connector

VSV for ACIS NO.2
Connector

VSV for ACIS NO.1 
Connector

VSV for ACIS NO.2

FI–58

–

ELECTRONIC FUEL INJECTION

VSV FOR EVAPORATIVE EMISSION (EVAP)

LEXUS RX300   (RM785E)

VSV FOR EVAPORATIVE EMISSION (EVAP)

COMPONENTS