Toyota Sequoia (2005). Manual - part 446

DI3DP–10

I28395

ECM

Transponder Key Coil

Transponder Key Amplifier

Instrument
Panel J/B 

 IGN Fuse

Engine Room J/B

 ECU–B Fuse

 EFI No. 1 Fuse

Transponder Key ECU

Combination Meter 

 Security Indicator Light

 MIL

DLC3

(Located behind the combination meter)

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

DI–1579

1773

PARTS LOCATION

DIABC–03

I24830

ECM

T16
Transponder Key ECU

IMI

IMO

16

15

P – G

11

10

EFIO

EFII

L – Y

E5

E5

DI–1580

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

1774

CIRCUIT INSPECTION

DTC

99

Engine Immobiliser System Malfunction

CIRCUIT DESCRIPTION

This DTC is indicated when a DTC is output from the transponder key ECU, or when there is an open or short
circuit in the wire harness between the transponder key ECU and the ECM.
If the DTC is output after replacing the transponder key ECU or ECM, carry out the ECU communication ID
registration.

DTC No.

DTC Detecting Condition

Trouble Area

99

Error in communication between ECM and transponder key

ECU, or in communication line.

Communication ID is different in communication with trans-

ponder key ECU.

ECU communication ID has not been registered

Transponder key ECU

ECM

Wire harness

WIRING DIAGRAM

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

DI–1581

1775

INSPECTION PROCEDURE

1

Has ECU communication ID registration been carried out?

 (See page 

BE–137

)

NO

Carry out ECU communication ID registration
again.

YES

2

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

IN–35

)

NG

Repair or replace harness or connector.

OK

3

Does the system operate normally after replacement of transponder key ECU?

YES

Replace transponder key ECU.

NO

Replace ECM

 

(See page 

IN–35

).

I24832

Transponder Key ECU

Body ECU

KSW

Y–G

T16

9

KSW2 B5

15

DI–1582

–

DIAGNOSTICS

ENGINE IMMOBILISER SYSTEM

1776

Code 11 is not output

CIRCUIT DESCRIPTION

The transponder key ECU outputs DTC 11 when the key unlock warning switch is ON (key is inserted).
HINT:
DTC 11 is a normal code.

DTC No.

DTC Detecting Condition

Trouble Area

11

Key unlock warning switch operates normally.

Unlock warning switch

Transponder key ECU

Wire harness

WIRING DIAGRAM

DIABD–03