Lexus ES300 (2002 year). Manual - part 400

A54396

VG

E2G

A55005

VG

E2G

E2

E9

A53763

E2 E2G

05-34

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

187

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

4

CHECK HARNESS AND CONNECTOR(ECM  -  INTAKE AIR FLOW METER)

(a)

Disconnect the intake air flow meter connector.

(b)

Disconnect the ECM E9 connector.

(c)

Check for open between the terminals VG of the intake air
flow meter harness side connector and VG of the ECM
connector.
Resistance: 1 

Ω

 or less

(d)

Check for open between the terminals E2G of the intake
air flow meter harness side connector and E2G of the
ECM connector.
Resistance: 1 

Ω

 or less

(e)

Check for short between the terminals VG and E2G of the
ECM connector.
Resistance: 1

 

M

Ω

 or more

(f)

Check for short between the terminals E2G and E2 of the
ECM connector.
Resistance: 1 M

Ω

 or more

NG

REPAIR OR REPLACE HARNESS AND
CONNECTOR

OK

REPLACE INTAKE AIR FLOW METER SUB-ASSY

5

INSPECT ECM

(a)

Check for open between the terminals E2G and E2 of the
ECM connector.
Resistance: 1 

Ω

 or less

NG

CHECK AND REPLACE ECM

OK

A54396

VG

E2

A55005

VG

E2G

E2

E9

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-35

188

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

6

CHECK HARNESS AND CONNECTOR(ECM  -  INTAKE AIR FLOW METER)

(a)

Disconnect the intake air flow meter connector.

(b)

Disconnect the ECM E9 connector.

(c)

Check for open  between the terminals VG of the intake
air flow meter harness side connector and VG of the ECM
connector.
Resistance: 1 

Ω

 or less

(d)

Check for open between the terminals E2 of the intake air
flow meter harness side connector and E2 of the ECM
connector.
Resistance: 1 

Ω

 or less

(e)

Connect the ECM connector.

(f)

Check for short between the terminals VG and E2G of the
ECM connector.
Resistance: 1 M

Ω

 or more

NG

REPAIR OR REPLACE HARNESS AND
CONNECTOR

OK

REPLACE INTAKE AIR FLOW METER SUB-ASSY

A59669

+B

E6

E9

E2G

A59656

3

A54396

E2G

05-36

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

189

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

7

CHECK HARNESS AND CONNECTOR(E.F.I. ECU RELAY  -  INTAKE AIR FLOW
METER)

(a)

Disconnect the battery negative (-) terminal.

(b)

DIsconnect the ECM E6 connector.

(c)

Check for open between the terminals +B of the ECM
connector and 3 of the E.F.I. ECM relay installation relay
block.
Resistance: 1 

Ω

 or less

NOTICE:
Do not insert the tester leads so hard in the procedure (c),
or the holder may be damaged.
(d)

DIsconnect the ECM E9 connector.

(e)

Check for open between the terminals E2G of the intake
air flow meter harness side connector and E2G of the
ECM connector.
Resistance: 1 

Ω

 or less

NG

CHECK AND REPLACE HARNESS AND
CONNECTOR

OK

CHECK FOR ECM POWER SOURCE CIRCUIT

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-37

190

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

DTC

P0101

MASS AIR FLOW CIRCUIT
RANGE/PERFORMANCE PROBLEM

CIRCUIT DESCRIPTION

Refer to DTC P0100 on page 

05-31

.

DTC No.

DTC Detecting Condition

Trouble Area

P0101

Conditions (a), (b) and (c) continue 10 sec. or more with en-
gine speed NE < 900: (2 trip detection logic)

(a) Throttle valve fully closed

(b) Intake air flow meter output > 2.2 V

(c) THW 

 70



C

Intake air flow meter

P0101

Conditions (a) and (b) continue 10 sec. or more with engine
speed 1,500 rpm or more: (2 trip detection logic)

(a) VTA 

 0.63 V

(b) Intake air flow meter output < 1.06 V

Intake air flow meter

INSPECTION PROCEDURE

HINT:
Read freeze frame data using hand-held tester or OBD II scan tool. Because freeze frame records the en-
gine conditions when the malfunction is detected. When troubleshooting, it is useful for determining whether
the vehicle was running 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

CHECK OTHER DTC OUTPUT(BESIDES DTC P0101)

NO

REPLACE INTAKE AIR FLOW METER
SUB-ASSY

YES

GO TO RELEVANT DTC CHART

051LV-07