Lexus ES300 (2002 year). Manual - part 374

A59661

E2

SPD

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-1 15

268

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

INSPECTION PROCEDURE

HINT:
Read freeze frame data using the hand-held tester or OBD II scan tool, as freeze frame data records the
engine 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

READ VALUE OF VEHICLE SPEED VALUE(SPEED METER)

(a)

Drive the vehicle and check if the operation of the speedometer in the combination meter is normal.

HINT:
The vehicle speed sensor is operating normally if the speedometer display is normal.

NG

CHECK SPEED METER CIRCUIT 
(See page 

05-1052

)

OK

2

CHECK HARNESS AND CONNECTOR(SPD  -  E2)

(a)

Check continuity between the terminals SPD and E2 of
the ECM connector.
Resistance: 1 M

Ω

 or more

NG

REPAIR OR REPLACE HARNESS AND
CONNECTOR

OK

A59661

E2

SPD

Turn Wheel

4.5-5.5V

0V

A50598

05-1 16

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

269

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

3

INSPECT ECM(SPD - E2)

(a)

Shift the lever to the neutral position.

(b)

Jack up the vehicle.

(c)

Turn the ignition switch ON.

(d)

Measure the voltage between terminal SPD and E2 of the
ECM connector with turning the wheel slowly.
Voltage: Generated intermittently

NG

REPAIR OR REPLACE HARNESS AND
CONNECTOR

OK

CHECK AND REPLACE ECM

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-1 17

270

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

DTC

P0505

IDLE CONTROL SYSTEM MALFUNCTION

CIRCUIT DESCRIPTION

The idle speed is controlled by the Electric Throttle Control System (ETCS).
ETCS is composed of the throttle motor to operate the throttle valve to connect the throttle motor with the
throttle valve, the throttle position sensor to detect the opening angle of the throttle valve, the accelerator
pedal position sensor to detect the accelerator pedal position, the ECM to control the ETCS and the one
valve type throttle body.
The ECM controls the throttle motor to make the throttle valve opening angle properly for the target idle
speed.

DTC No.

DTC Detection Condition

Trouble Area

P0505

Idle speed continues to vary greatly from target speed
(2 trip detection logic)

Throttle body assy

Air induction system

PCV hose connection

ECM

INSPECTION PROCEDURE

HINT:
Read freed 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.

1

CHECK OTHER DTC OUTPUT(BESIDES DTC P0505)

(a)

Read the DTC using the hand-held tester or OBD II scan tool.

YES

GO TO RELEVANT DTC CHART

NO

2

CHECK AIR INDUCTION SYSTEM

NG

REPAIR OR REPLACE AIR INDUCTION SYSTEM

OK

3

CHECK CONNECTION OF PCV HOSE

NG

REPAIR OR REPLACE PCV HOSE

OK

055CJ-04

A57005

A57012

A53763

VTA1

E2

05-1 18

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

271

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

4

INSPECT THROTTLE BODY ASSY

(a)

Inspect the throttle control motor for operating sound.
(1)

When turning the accelerator pedal position sensor
lever, check the running sound of the motor. Also,
check that there is no friction sound.

If operation is not as specified, check the throttle control motor,
wiring and ECM.

(b)

Inspect the accelerator pedal position sensor.
(1)

Connect the hand-held tester or OBDll scan tool to
the DLC3.

(2)

Check that the check engine warning light does not
light up.

(3)

When turning the accelerator pedal position sensor
lever to the full- open position, check that the
throttle valve opening percentage (THROTTLE
POS) of the CURRENT DATA showns the standard
value.

Standard throttle valve opening percentage:
60 % or more

If operation is not as specified, check that the accelerator pedal
position sensor, wiring and ECM.
If you have no hand-held tester, measure voltage between ter-
minals VTA1 and E2 of the ECM connector (See page 

05-27

).

(c)

Inspect the idle speed.
(1)

Start the engine and check that the MIL does not
light up.

(2)

Allow the engine to warm up to normal operating
temperature.

(3)

Turn the A/C conditioning ON to OFF, and check the
idle speed.

Idle speed (Transmission in neutral): 600 

±

 50 rpm

NOTICE:
Perform inspection under condition without electrical load.
(d)

After checking the above (b) to (d), perform the driving
test and check that there is no sense of incongruity.

NG

REPLACE THROTTLE BODY ASSY

OK