Lexus ES300 (1997 year). Service manual — part 353

BE3840

Q07660

D00015

ON

OD

–

DIAGNOSTICS

AUTOMATIC TRANSAXLE

DI–189

341

1997 LEXUS ES300 (RM511U)

2

Check voltage between terminal OD of cruise control ECU harness side connec-
tor and body ground.

PREPARATION:
(a)

Disconnect the cruise control ECU connector.

(b)

Turn the ignition switch ON.

CHECK:
Measure voltage between terminal OD of cruise control ECU
harness side connector and body ground.
OK:

Voltage: 10

∼

14 V

OK

Check and replace the cruise control ECU.

NG

3

Check harness and connector between cruise control ECU and ECM.

NG

Repair or replace the harness or connector.

OK

Check and replace the ECM.

D00039

ECM

6

E7

OD2

B+

G–O

IG3

11

J6

C

C

C

O2

O/D Main Switch

J5

IF

O/D Indicator Light

C12

C8

7

12

R–L

R–L

J4

D

D

From Ignition Switch

1 1K

2 1D

GAUGE

J/B No.1

G–O

O2

A

A

W–B

W–B

DI–190

–

DIAGNOSTICS

AUTOMATIC TRANSAXLE

342

1997 LEXUS ES300 (RM511U)

O/D Main Switch & O/D OFF Indictor Light Circuit

CIRCUIT DESCRIPTION

The O/D main switch contacts go open when the switch is pushed in and go closed when it is pushed out.
In O/D main switch at OFF position, the O/D OFF indicator light lights up, and the ECM prohibits shifting over-
drive.

WIRING DIAGRAM

DI0D1–01

D00054

ON

O/D Main Switch

OFF

ON

OFF

ON

–

DIAGNOSTICS

AUTOMATIC TRANSAXLE

DI–191

343

1997 LEXUS ES300 (RM511U)

INSPECTION PROCEDURE
O/D OFF indicator light does not light up

1

Check operation of O/D main switch.

PREPARATION:
Turn the ignition switch ON.
CHECK:
(a)

Check the O/D OFF indicator light when O/D main switch
is pushed in to ON.

(b)

Check the O/D OFF indicator light when O/D main switch
is pushed again to OFF.

OK:

(a) O/D OFF indicator light goes off
(b) O/D OFF indicator light lights up

NG

Go to step 4.

OK

2

Check OVRDRIVE CUT SW2 signal.

When using LEXUS hand–held tester
PREPARATION:
(a)

Remove the DLC3 cover.

(b)

Connect a LEXUS hand–held tester to the DLC3.

(c)

Turn the ignition switch ON and LEXUS hand–held tester
main switch ON.

CHECK:
Read the OVRDRIVE CUT SW2 signal on the LEXUS hand–
held tester.
OK:

O/D main switch condition

OVRDRIVE CUT SW2 signal

Pushed in

OFF

Pushed out

ON

D00059

ON

OD2

Q07595

2

4

DI–192

–

DIAGNOSTICS

AUTOMATIC TRANSAXLE

344

1997 LEXUS ES300 (RM511U)

When not using LEXUS hand–held tester
PREPARATION:
Turn the ignition switch ON.
CHECK:
Check voltage between terminal OD2 of ECM and body ground.
OK:

O/D main switch

Voltage

OFF

Below 1 V

ON

10

∼

14 V

OK

Proceed to next circuit inspection shown on
matrix chart (See page

DI–164

).

NG

3

Check harness and connector between O/D OFF indicator light and ECM
(See page

IN–27

).

NG

Repair or replace the harness or connector.

OK

Check the O/D main switch.

4

Check O/D main switch.

PREPARATION:
Disconnect the O/D main switch connector.
CHECK:
Check continuity between terminals 2 and 4 of O/D main switch
connector.
OK:

O/D main switch

Resistance

ON

∞

Ω

(open)

OFF

0

Ω

(continuity)

NG

Replace the O/D main switch.

OK