Toyota Sequoia (2005). Manual - part 448

I24834

F10
FL Block

1J

1C

Instrument Panel J/B

IG2

B–R

I18 
Ignition SW

Battery

5

6

B

B

W–R

AM2

2

17

IGN1

1C

1E

7

3

4

5

Transponder Key ECU

IG

2

2C

T16

2D

B–O

1

B–O

W–R

1

AM2

Engine Room J/B

Sub J/B No. 4

2

12

4D

4A

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

DI–1587

1781

Code 13 is not output

CIRCUIT DESCRIPTION

The transponder key ECU outputs DTC 13 when the ignition switch is ON.
HINT:
DTC 13 is a normal code.

DTC No.

DTC Detecting Condition

Trouble Area

13

Ignition switch operates normally.

Ignition switch

Transponder key ECU

Wire harness

WIRING DIAGRAM

DIABF–04

DI–1588

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

1782

INSPECTION PROCEDURE

1

Check ignition switch (See page 

BE–24

).

NG

Replace ignition switch.

OK

2

Check harness and connector between ignition switch and transponder key ECU
(See page 

IN–35

).

NG

Repair or replace harness or connector.

OK

Replace transponder key ECU (See page 

IN–35

).

I03114

T6
Transponder Key
Amplifier

13

T16

Transponder Key ECU

CODE

RXCK

TXCT

6

5

4

5

T16

4

T16

Y–G

LG

R–Y

RXCK

CODE

TXCT

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

DI–1589

1783

Code 21 or 22 is not output

CIRCUIT DESCRIPTION

The transponder key ECU outputs DTC 21 while the immobilizer system is deactivated by use of the master
key, and outputs DTC 22 while it is deactivated by use of the sub key.
HINT:
DTCs 21 and 22 are normal codes.

DTC No.

(See Page)

DTC Detecting Condition

Trouble Area

21, 22

Communication is normal.

Key

Transponder key ECU

Transponder key amplifier with key coil

Wire harness

WIRING DIAGRAM

DIABG–04

DI–1590

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

1784

INSPECTION PROCEDURE

1

Check whether the engine can be started with the master key and sub–key for
another vehicle of the same type.

RESULT:

A

All keys start the engine.

B

A specific key does not start the engine. In this case, DTC

21 or 22 is not stored in memory.

C

All keys do not start the engine. In this case, DTC 21 and 22

are not stored in memory.

A

No problem at this time.

HINT:
If the result is ”A”, confirm whether or not the customer has ever
inserted the key (without a transponder chip) of another vehicle
into the ignition key cylinder.

B

The transponder chip of a specific key is defec-
tive. Replace the key.

C

2

Check transponder key coil (See page 

BE–143

).

NG

Replace transponder key coil.

OK

3

Check harness and connector between transponder key ECU and transponder
key amplifier (See page 

IN–35

).

NG

Repair or replace harness or connector.

OK