Lexus ES300 (1997 year). Service manual — part 306

S04946

Ohmmeter

Continuity

1

3

2

5

Battery

CO–36

–

COOLING

COOLING FAN RELAY

953

1997 LEXUS ES300 (RM511U)

(c)

Inspect the No.3 cooling fan relay operation.
(1)

Apply battery voltage across terminals 1 and 2.

(2)

Using an ohmmeter, check that there is continuity
between terminals 3 and 5.

If there is no continuity, replace the relay.
(d)

Install the No.3 cooling fan relay.

DI094–01

Vehicle Brought to Workshop

Customer Problem Analysis P.

DI–2

Problem Symptom Confirmation

If the engine does not start, perform steps 10 and 12 first

Connect the OBD II scan tool or LEXUS hand–held tester to DLC3 P.

DI–3

If the display indicates a communication fault in the tool, inspect DLC3 P.

DI–3

Check DTC and Freezed Frame Data (Precheck)

Record or Print DTC and Freezed Frame Data P.

DI–3

Clear DTC and Freezed Frame Data P.

DI–3

Visual Inspection

Setting the Check Mode Diagnosis P.

DI–3

Symptom Simulation P.

IN–17

DTC Chart P.

DI–14

Problem Symptom Table P.

DI–22

Circuit Inspection P.

DI–23

Adjustment, Repair

DTC Check P.

DI–3

Titles inside

are titles of pages in

in the bottom portion. See the indicated
pages for detailes explanations.

this manual with the page number indicated

Malfunction
occurs.

Malfunction does not occur.

Parts Inspection

Check for Intermittent Problems P.

DI–3

Identification of Problem

Confirmation Test

End

1

2

3

4

5

6

7

10

8

9

11

12

13

15

14

16

Normal

Malfunction code.

17

Basic Inspection P.

DI–3

–

DIAGNOSTICS

ENGINE

DI–1

153

1997 LEXUS ES300 (RM511U)

ENGINE

HOW TO PROCEED WITH TROUBLESHOOTING

Troubleshoot in accordance with the procedure on the following page.

DI095–01

ENGINE CONTROL SYSTEM Check Sheet

Customer’s Name

Driver’s Name

Date Vehicle
Brought in

License No.

Model and Model
Year

Frame No.

Engine Model

Odometer Reading

km
miles

Problem Symptoms

Engine does
not Start

Difficult to
Start

Poor Idling

Poor
Driveability

Engine Stall

Others

Engine does not crank

No initial combustion

No complete combustion

Engine cranks slowly

Other

Incorrect first idle

Idling rpm is abnormal

High ( rpm)

Low ( rpm)

Rough idling

Other

Hesitation

Back fire

Muffler explosion (after–fire)

Surging

Knocking

Other

Soon after starting

After accelerator pedal depressed

After accelerator pedal released

During A/C operation

Shifting from N to D

Other

Dates Problem
Occurred

Problem Frequency

Condition When

Problem Occurs

Weather

Engine Operation

Engine Temp.

Place

Outdoor

Temperature

Constant

Sometimes ( times per day/month)

Once only

Other

Fine

Cloudy

Rainy

Snowy

Various/Other

Hot

Warm

Cool

Cold (approx.

°

F/

°

C)

Highway

Suburbs

Inner City

Uphill

Downhill

Rough road

Other

Cold

Warming up

After Warming up

Any temp.

Other

Starting

Just after starting ( min.)

Idling

Racing

Driving

Constant speed

Acceleration

Deceleration

A/C switch ON/OFF

Other

Condition of MIL

Remains on

Sometimes light up

Does not light up

Normal

Malfunction code(s) (code )

Freezed frame data ( )

Normal

Malfunction code(s) (code )

Freezed frame data ( )

Normal mode
(Precheck)

Check Mode

DTC Inspection

Inspector’s
Name

DI–2

–

DIAGNOSTICS

ENGINE

154

1997 LEXUS ES300 (RM511U)

CUSTOMER PROBLEM ANALYSIS CHECK

DI096–01

FI0534

S05335

LEXUS Hand–Held Tester

DTC

–

DIAGNOSTICS

ENGINE

DI–3

155

1997 LEXUS ES300 (RM511U)

PRE–CHECK

1.

DIAGNOSIS SYSTEM

(a)

Description
When troubleshooting OBD II vehicles, the only differ-
ence from the usual troubleshooting procedure is that you
connect to the vehicle the OBD II scan tool complying with
SAE J1978 or LEXUS hand–held tester, and read off vari-
ous data output from the vehicle’s ECM.
OBD II regulations require that the vehicle’s on–board
computer lights up the Malfunction Indicator Lamp (MIL)
on the instrument panel when the computer detects a
malfunction in the computer itself or in drive system com-
ponents which affect vehicle emissions. In addition to the
MIL lighting up when a malfunction is detected, the appli-
cable Diagnostic Trouble Codes (DTC) prescribed by
SAE J2012 are recorded in the ECM memory (See page

DI–14

).

If the malfunction does not reoccur in 3 trips, the MIL goes
off but the DTC remain recorded in the ECM memory.

To check the DTC, connect the OBD II scan tool or LEXUS
hand–held tester to Data Link Connector 3 (DLC3) on the
vehicle. The OBD II scan tool or LEXUS hand–held tester
also enables you to erase the DTC and check freezed
frame data and various forms of engine data (For operat-
ing instructions, see the OBD II scan tool’s instruction
book.).
DTC include SAE controlled codes and manufacturer
controlled codes. SAE controlled codes must be set as
prescribed by the SAE, while manufacturer controlled
codes can be set freely by the manufacturer within the
prescribed limits (See DTC chart on page

DI–14

).

The diagnosis system operates in normal mode during
normal vehicle use. It also has a check mode for techni-
cians to simulate malfunction symptoms and trouble-
shoot. Most DTC use 2 trip detection logic* to prevent er-
roneous detection, and ensure thorough malfunction
detection. By switching the ECM to check mode when
troubleshooting, the technician can cause the MIL to light
up for a malfunction that is only detected once or momen-
tarily (LEXUS hand–held tester only).
(See page

DI–14

)

*2 trip detection logic: When a logic malfunction is first de-
tected, the malfunction is temporarily stored in the ECM
memory. If the same malfunction is detected again during
the second drive test, this second detection causes the
MIL to light up.
The 2 trip repeats the same mode a 2nd time (However,
the IG switch must be turned OFF between the 1st trip and
2nd trip.).