Lexus ES300 (2002 year). Service manual - part 321

056DH-01

-

DIAGNOSTICS

AIR CONDITIONING SYSTEM

05-461

614

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

DIAGNOSTIC TROUBLE CODE CHART

If malfunction code is displayed during the DTC check (sensor check), check the circuit listed for that code
in the table below (Proceed to the page given for that circuit).

DTC No.

(See Page)

Detection Item

Trouble Area

Memory

00

Normal

-

-

11*

1

(

05-470

)

Room temperature sensor circuit

Room temp. sensor

A/C amplifier (Heater Control Housing)

Harness or connector between room temp. sensor and A/C
amplifier (Heater Control Housing)



(8.5 min. or more)

12*

2

(

05-473

)

Ambient temperature sensor circuit

Ambient temp. sensor

Harness or connector between ambient temp. sensor and
A/C amplifier (Heater Control Housing)

A/C amplifier (Heater Control Housing)



(8.5 min. or more)

13

(

05-475

)

Evaporator temperature sensor circuit

Evaporator temp. sensor

Harness or connector between evaporator temp. sensor and
A/C amplifier (Heater Control Housing)

A/C amplifier (Heater Control Housing)



(8.5 min. or more)

14

(

05-478

)

Water temperature sensor circuit

Harness or connector between ECM and A/C amplifier
(Heater Control Housing)

ECM

A/C amplifier (Heater Control Housing)

-

21*

3

(

05 480

)

Solar sensor circuit (short)
(Passenger side)

Solar sensor

Harness or connector between solar sensor and A/C amplifi-
er (Heater Control Housing) , body ECU



(8.5 min. or more)

(

05-480

)

Solar sensor circuit (open)

er (Heater Control Housing) , body ECU

Body ECU

A/C amplifier (Heater Control Housing)

-

22*

4

(

05-483

)

Compressor lock sensor circuit

Compressor Drive Belt

Compressor lock sensor

Compressor

ECM

Harness or connector between ECM and A/C lock sensor,
A/C amplifier (Heater Control Housing)

A/C amplifier (Heater Control Housing)

-

23

(

05-486

)

Pressure switch circuit

Pressure switch

A/C amplifier (Heater Control Housing)

Harness or connector between pressure switch and A/C
amplifier (Heater Control Housing)

-

24*

3

(

05 489

)

Solar sensor circuit (short)
(Driver side)

Solar sensor

Harness or connector between solar sensor and A/C amplifi-
er (Heater Control Housing) , body ECU



(8.5 min. or more)

(

05-489

)

Solar sensor circuit (open)

er (Heater Control Housing) , body ECU

Body ECU

A/C amplifier (Heater Control Housing)

-

31

(

05-492

)

Air mix damper position sensor circuit
(Passenger side)

Air mix damper position sensor

A/C amplifier (Heater Control Housing)

Harness or connector between air mix damper position sen-
sor and A/C amplifier (Heater Control Housing)

-

32

(0

05-495

)

Air inlet damper position sensor circuit

Air inlet damper position sensor (Recirculation damper servo
sub-assy)

A/C amplifier (Heater Control Housing)

Harness or connector between air inlet damper position
sensor and A/C amplifier (Heater Control Housing)



(1 min. or more)

05-462

-

DIAGNOSTICS

AIR CONDITIONING SYSTEM

615

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

33

(

05-498

)

Air outlet damper position sensor circuit

Air outlet damper position sensor (Mode damper servo sub-
assy)

A/C amplifier (Heater Control Housing)

Harness or connector between air outlet damper position
sensor (Mode damper servo sub-assy) and A/C amplifier
(Heater Control Housing)



(1 min. or more)

36

(

05-501

)

Air mix damper position sensor circuit
(Driver side)

Air mix damper position sensor

A/C amplifier (Heater Control Housing)

Harness or connector between air mix damper position sen-
sor and A/C amplifier (Heater Control Housing)



(1 min. or more)

41

(

05-504

)

Air mix damper control servomotor
(Passenger side)

Air mix control servomotor

Harness or connector between air mix damper control ser-
vomotor and A/C amplifier (Heater Control Housing)

A/C amplifier (Heater Control Housing)



(15 sec.)

42

(

05-508

)

Air inlet damper control servomotor

Air inlet control servomotor (Recirculation damper servo
sub-assy)

Harness or connector between air inlet damper control ser-
vomotor  and A/C amplifier (Heater Control Housing)

A/C amplifier (Heater Control Housing)



(15 sec.)

43

(

05-512

)

Air outlet damper control servomotor

Air outlet control servomotor (Mode damper servo sub-
assy)

Harness or connector between air outlet damper control
servomotor  (Mode damper servo sub-assy) and A/C ampli-
fier (Heater Control Housing)

A/C amplifier (Heater Control Housing)



(15 sec.)

46

(

05-516

)

Air mix damper control servomotor
(Driver side)

Air mix control servomotor

Harness or connector between air mix damper control ser-
vomotor and A/C amplifier (Heater Control Housing)

A/C amplifier (Heater Control Housing)



(15 sec.)

63*

6

(

05-520

)

Seat heater
(Driver side)

Seat  heater

Harness or connector between seat heater and A/C amplifier
(Heater Control Housing)

A/C amplifier (Heater Control Housing)

-

64*

6

(

05-523

)

Seat heater
(Passenger side)

Seat  heater

Harness or connector between seat heater and A/C amplifier
(Heater Control Housing)

A/C amplifier (Heater Control Housing)

-

HINT:

*1

: If the room temp. is approx. -18.6

°

C (-3.7

°

F) or lower, trouble code 11 may be output even though

the system is normal.

*2

: If the ambient temp. is approx. -52.9

°

C (-61.4

°

F) or lower, a malfunction code may be output even

though the system is normal.

*3

: If the check is being performed in a dark place, DTC 21, 24 (solar sensor circuit abnormal) could

be displayed.

*4

: Compressor lock (DTC22) is indicated only for a current occurring malfunction (See page 

05-483

).

To confirm DTC 22, perform the following steps.
(1)

With the engine ON, enter the DTC check mode.

(2)

Press the F/R switch to enter actuator check mode, and set the operation to Step No. 3.

(3)

Press the AUTO switch to return to DTC check mode.

(4)

The DTC is displayed after approx. 3 sec.

*5

: The A/C amplifier (Heater Control Housing) memorizes the DTC of the respective malfunction it has

occurred for the period of the time indicated in the brackets.

*6

: Even though the system is in good condition, DTC is output when the seat sensor temperature

senses -40



C (-40



F) and over 99



C (210.2



F).

056CJ-01

I31446

Compressor and Magnetic Clutch

Pressure SW

Condenser

Cooler (Ambient Temperature Sensor) Thermistor

Cooler (Solar Sensor) Thermistor
(Driver Side, Passenger Side)

Engine Room J/B and R/B

 HTR Relay

 MG GLT Relay

 HTR Fuse

Heater Control Housing
Sub-assy
(A/C Control Assembly)

 Air Conditioner

Amplifier

ECM

Driver Side J/B

 ECU-B Fuse

 HTR Fuse

Cooler (Room  Temperature Sensor)
Thermistor

Seat Heater Back

Seat Heater Cushion

-

DIAGNOSTICS

AIR CONDITIONING SYSTEM

05-463

616

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)

LOCATION

I31447

Expansion Valve

Air Outlet Control Servomotor 
(Mode Damper Servo Sub-assy)

Blower Motor
Linear Controller
(Blower Motor 
Control)

Evaporator

Heater Radiator

Air Mix Damper Control
Servomotor
(Passenger Side)

Blower w/ Fan Motor

Air Inlet Control Servomotor
(Recirculation Damper 
Servo Sub-assy)

Evaporator
Temperature Sensor
(Cooler Thermistor No,1)

Air Mix Damper Control
Servomotor
(Driver Side)

05-464

-

DIAGNOSTICS

AIR CONDITIONING SYSTEM

617

2002 LEXUS ES300 REPAIR MANUAL   (RM911U)