Toyota Sequoia (2005). Manual - part 644

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

DI–2371

2565

INSPECTION PROCEDURE

1

Check operation of speedometer.

CHECK:
Check that the speedometer operates normally.

NG

Proceed to combination meter troubleshooting
(See page 

BE–2

).

OK

2

Check harness and connector between combination meter and integration con-
trol and panel (See page 

IN–35

).

NG

Repair or replace harness or connector.

OK

Replace integration control and panel.

I28848

IGN

I22

3

Y–G

B

23

Combination Meter

TACH

Integration Control
and Panel

E5

Y–G

1

Y–G

C5

ECM

J17
J/C

B

B

J14

D

J14

F

J15

F

DI–2372

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

2566

Igniter Circuit

CIRCUIT DESCRIPTION

The integration control and panel monitors the engine speed through signals sent from the igniter. It uses
these signals and compressor speed signals to detect the compressor lock condition.

WIRING DIAGRAM

DI3WE–19

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

DI–2373

2567

INSPECTION PROCEDURE

1

Check operation of tachometer.

CHECK:
Check that the tachometer operates normally.

NG

Proceed to combination meter troubleshooting
(See page 

BE–2

).

OK

2

Check harness and connector between ECM and integration control and panel
(See page 

IN–35

).

NG

Repair or replace harness or connector.

OK

3

Check harness and connector between combination meter and integration con-
trol and panel (See page 

IN–35

).

NG

Repair or replace harness or connector.

OK

Replace integration control and panel.

Duty Ratio =

A + B

A

x 100 (%)

ON

OFF

A

B

1 cycle

Blower Level

0

Si duty (%)

LO

M1

M2

HI

29.2 42.4

55.5

100

M3

70.9

I15873

Integration Control
and Panel

BLW

From 
Heater Relay

W–B

IG

A

GND

VM

SI

J18
J/C

+B

3

4

L–B

1

G–B

I19

2

4

B3
Blower
Motor (Front)

1

2

L–W

L–B

L–B

B4
Blower Motor
Linear Controller

DI–2374

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

2568

Blower Motor Circuit (Front A/C)

CIRCUIT DESCRIPTION

The blower motor is operated by signals from the integration
control and panel. Blower motor speed signals are transmitted
by changes in the Duty Ratio.
Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle.
For example, if A is the period of continuity in one cycle, and B
is the period of non–continuity, then.

WIRING DIAGRAM

DI7SL–08