Lexus ES300 (2002 year). Manual - part 391

A53769

BATT

E2

A59659

E.F.I. (20 A)

05-162

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

315

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

1

INSPECT ECM

(a)

Measure the voltage between terminal BATT and E2 of
the ECM connector.
Voltage: 9 -

 

14 V

OK

CHECK AND REPLACE ECM

NG

2

CHECK FUSE(FOR E.F.I.)

(a)

Check the continuity of the E.F.I. fuse.
Result: Continuity

NG

CHECK FOR SHORT IN ALL HARNESS AND
COMPONENTS CONNECTED EFI FUSE

OK

REPAIR OR REPLACE HARNESS AND CONNECTOR

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-163

316

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

DTC

P1633

ECM MALFUNCTION (ETCS CIRCUIT)

CIRCUIT DESCRIPTION

DTC No.

DTC Detecting Condition

Trouble Area

P1633

ECM malfunction

ECM

INSPECTION PROCEDURE

HINT:
Read freeze frame data using hand-held tester. Because freeze frame records the engine conditions when
the malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was run-
ning or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the
malfunction.

1

REPAIR OR REPLACE ECM

055CF-03

05-164

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

317

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

DTC

P1656

OCV CIRCUIT MALFUNCTION

DTC

P1663

OCV CIRCUIT MALFUNCTION(BANK2)

CIRCUIT DESCRIPTION

Refer to DTC P1349 on page 

05-152

..

DTC No.

DTC Detecting Condition

Trouble Area

P1656
P1663

Open or short in oil control valve circuit

Open or short in oil control valve circuit

Oil control valve

 ECM

WIRING DIAGRAM

Reter to DTC P1349 on page 

05-152

.

INSPECTION PROCEDURE

HINT:
Read freeze frame data using hand-held tester. Because freeze frame records the engine conditions when
the malfunction is detected, when troubleshooting it is useful for determining whether the vehicle was run-
ning or stopped, the engine warmed up or not, the air-fuel ratio lean or rich, etc. at the time of the malfunction.

Hand-held  Tester:

1

PERFORM ACTIVE TEST BY CHECK OCV CIRCUIT

(a)

Warmed up the engine.

(b)

Select ACTIVE TEST on the hand-held tester.

(c)

Check the engine speed when the OCV is made to operate by the hand-held tester.
Engine speed:
OCV is OFF: Normal engine speed
OCV is ON: Rough idle or engine stall

HINT:
DTCs P1656 and P1663 also output after the foreign object is caught in some part of the system in the engine
oil and the system returns to normal in a short time. As engine ECM operates so that foreign objects are
ejected, there is no problem about VVT. There is also no problem since the oil filter should get the foreign
object in the engine oil.

OK

CHECK FOR INTERMITTENT PROBLEMS

NG

2

CHECK OPERATION OF OCV

(a)

Start the engine and warmed it up.

(b)

Apply battery positive voltage between terminals of the OCV.

(c)

Check the engine speed.
Result: Rough idle or engine stalled.

NG

REPLACE OCV

OK

051XB-07

A54408

OC1+

OC1-

OC2+

OC2-

E8

E2

1

2

A50603

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-165

318

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

3

INSPECT ECM (See page 

05-152

)

NG

CHECK AND REPLACE ECM

OK

4

CHECK HARNESS AND CONNECTOR(OCV  -  ECM)

(a)

Disconnect the engine ECM E8 connector.

(b)

Disconnect the OCV connector.

(c)

Check for open between the terminals OC1+ of the ECM
connecter and 1 of the OCV(RH) connector.
Resistance: 1 

Ω

 or less

(d)

Check for open between the terminals OC1- of the ECM
connecter and 2 of the OCV(RH) connector.
Resistance: 1 

Ω

 or less

(e)

Check for open between the terminals OC2+ of the ECM
connecter and 1 of the OCV(LH) connector.
Resistance: 1 

Ω

 or less

(f)

Check for open between the terminals OC2- of the ECM
connecter and 2 of the OCV(LH) connector.
Resistance: 1 

Ω

 or less

(g)

Check for short between the terminals
OC1+,OC1-,OC2+,OC2-  and E2 of the ECM connector.
Resistance: 1 M

Ω

 or more

NG

REPAIR OR REPLACE HARNESS AND
CONNECTOR

OK

CHECK FOR INTERMITTENT PROBLEMS