Lexus ES300 (1997 year). Manual — part 332

–

DIAGNOSTICS

ENGINE

DI–105

257

1997 LEXUS ES300 (RM511U)

INSPECTION PROCEDURE

HINT:If DTC P0441, P0446 or P0450 is output after DTC P0440, first troubleshoot DTC P0441, P0446 or
P0450. If no malfunction is detected, troubleshoot DTC P0440 next.

1

Check voltage between terminals VC and E2 of ECM connector
(See page

DI–87

,

IG–1

).

NG

Check and replace ECM (See page

IN–27

).

OK

2

Check voltage between terminals PTNK and E2 of ECM connectors
(See page

DI–87

,

SF–6

).

OK

Check and replace ECM (See page

IN–27

).

NG

3

Check for open and short in harness and connector between vapor pressure
sensor and ECM (See page

IN–27

).

NG

Repair or replace harness or connector.

OK

Replace vapor pressure sensor.

A00223

Vehicle Speed
Sensor

Combination
Meter

ECM

Transaxle

4–Pulse

4–Pulse

Vehicle Speed Sensor

Q00515 Q00514

S05718

Combination
Meter

J17
Junction
Connector

10

C9

E7

3

IJ1

V–W

V–W

V–W

ECM

SPD

5V

C

C

12

E01

DI–106

–

DIAGNOSTICS

ENGINE

258

1997 LEXUS ES300 (RM511U)

DTC

P0500

Vehicle Speed Sensor Malfunction

CIRCUIT DESCRIPTION

The vehicle speed sensor outputs a 4–pulse signal for every revolution of the rotor shaft, which is rotated
by the transmission output shaft via the driven gear. After this signal is converted into a more precise rectan-
gular waveform by the waveform shaping circuit inside the combination meter, it is then transmitted to the
ECM. The ECM determines the vehicle speed based on the frequency of these pulse signals.

DTC No.

DTC Detecting Condition

Trouble Area

P0500

No vehicle speed sensor signal to ECM under conditions (a)

and (b):

(2 trip detection logic)

(a) Park/neutral position switch is OFF

(b) Vehicle is being driven

Open or short in vehicle speed sensor circuit

Vehicle speed sensor

Combination meter

ECM

WIRING DIAGRAM

DI09Y–01

P23875

E7

SPD

–

DIAGNOSTICS

ENGINE

DI–107

259

1997 LEXUS ES300 (RM511U)

INSPECTION PROCEDURE

1

Check operation of speedometer.

CHECK:
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 speedometer circuit.

OK

2

Check for short in harness and connector between terminal SPD of ECM and
body ground.

PREPARATION:
(a)

Remove the glove compartment (See page

SF–65

).

(b)

Disconnect the E7 connector of ECM.

CHECK:
Check continuity between terminal SPD of ECM and body
ground.
OK:

No continuity (1 M

Ω

or higher)

NG

Repair or replace harness or connector.

OK

A00235

E7

ON

SPD(+)

BE6653
P23876

DI–108

–

DIAGNOSTICS

ENGINE

260

1997 LEXUS ES300 (RM511U)

3

Check voltage between terminal SPD of ECM connector and body ground.

PREPARATION:
Turn ignition switch ON.
CHECK:
Measure voltage between terminal SPD of ECM connector and
body ground.
OK:

Voltage: 9

∼

14 V

NG

Check for open in harness and connector
between junction connector (J17) and ECM
(See page

IN–27

).

OK

4

Check for open in harness and connector between junction connector (J17) and
combination meter (See page

IN–27

).

NG

Repair or replace harness or connector.

OK

Check and replace ECM (See page

IN–27

).