Toyota Sequoia (2005). Manual - part 646

I28847

RrVM

I21

Integration Control and Panel:

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

DI–2379

2573

3

Check voltage between terminal RrVM of integration control and panel and body
ground.

PREPARATION:
Remove the integration control and panel with connectors still
connected.
CHECK:
(a)

Turn the ignition switch to ON.

(b)

Operate the rear A/C blower motor.

(c)

Measure the voltage between terminal RrVM of the in-
tegration control and panel and body ground, when the
blower switch is operated as shown in the table below.

OK:

Blower speed

Voltage

LO

7.2 V

ME

4.2 V

HI

0.5 V

OK

Proceed to next circuit inspection shown in
problem symptoms table (See page 

DI–2304

).

NG

I07763

1

2

4

I07764

3

4

DI–2380

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

2574

4

Check power transistor.

PREPARATION:
Remove the power transistor (See page 

AC–84

).

CHECK:
(a)

Connect the positive (+) lead from the battery to terminal
1 through a 12 V – 3.4 W test bulb and the negative (–)
lead to terminal 2.

(b)

Check the test bulb lights up when another positive (+)
lead is connected to terminal 4 through a 12 V – 3.4 W test
bulb.

OK:

Test bulb lights up.

CHECK:
Measure the resistance between terminals 3 and 4.
OK:

Resistance: 2.0 to 2.4 k

Ω

NG

Replace power transistor.

OK

5

Check harness and connector between integration control and panel and power
transistor, power transistor and body ground (See page 

IN–35

).

NG

Repair or replace harness or connector.

OK

Replace integration control and panel.

I28845

ECM

E5

E5

G–B

Integration Control 
and Panel

I22 ACT

AC1

8

25

24

L–W

2

2

1

5

MG CLT Relay

J3 J/C

15

IG4

C

C

Engine Room J/B

2

2C

4

2G

3

A3 
A/C Magnetic Clutch 
and Lock Sensor

R–Y

IA1

LG–B

5

4

Engine Room R/B No. 2

2

2

2

G–Y

MGC

5

I19

I22

ACT

AC1

IA5

R–Y

1

L–W

L–W

R–Y

L

L

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

DI–2381

2575

Compressor Circuit

CIRCUIT DESCRIPTION

The integration control and panel outputs the magnetic clutch ON signal from terminal AC1 to the ECM.
When the ECM receives this signal, it sends a signal from terminal ACT and switches the A/C magnetic clutch
relay ON. This turns the A/C magnetic clutch on.

WIRING DIAGRAM

DIAA8–03

DI–2382

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

2576

INSPECTION PROCEDURE

1

Read value of hand–held tester.

PREPARATION:
(a)

Connect the hand–held tester to the DLC3.

(b)

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

CHECK:
Select the item below in the DATA LIST, and read the displays on the hand–held tester.
ENGINE AND ECT / ALL:

Item

Measurement Item / Display

(Range)

Normal Condition

Diagnostic Note

A/C SIG

A/C signal / ON or OFF

A/C SW Pushed: ON

A/C SW Released: OFF

–

HINT:
Check with the engine running.
OK:

The display is as specified in the normal condition.

  NG

Go to step 8.

OK

2

Read value of hand–held tester.

PREPARATION:
(a)

Connect the hand–held tester to the DLC3.

(b)

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

CHECK:
Select the item below in the DATA LIST, and read the displays on the hand–held tester.
ENGINE AND ECT / ALL:

Item

Measurement Item / Display

(Range)

Normal Condition

Diagnostic Note

A/C MAG CLUTCH

A/C magnet clutch / ON or OFF

A/C SW ON: ON

A/C SW OFF: OFF

–

HINT:
Check with the engine running.
OK:

The display is as specified in the normal condition.

  NG

Replace ECM (See page 

SF–80

).

OK