Last Modified: 11-29-2007 1.6 C
Service Category: Vehicle Interior Section: Theft Deterrent/Keyless Entry
Model Year: 2008 Model: Sequoia Doc ID: RM000002X2F00CX
Title: THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM: DESCRIPTION (2008 Sequoia)

DTC

B279A

Theft Deterrent System Communication Line High Fixation

DESCRIPTION

If the communication line (EFIO-IMI) to the transponder key ECU is stuck on HI output, the ECM outputs this DTC.

DTC Code

DTC Detection Condition

Trouble Area

B279A

When communication line (EFIO-IMI) between ECM and transponder key ECU is stuck on HI output for 6 seconds or more
  • Harness or connector
  • Transponder key ECU
  • ECM

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTC THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM: DTC CHECK / CLEAR (2008 Sequoia) .

NEXT

2.

CHECK FOR DTC

(a) Check for DTC THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM: DTC CHECK / CLEAR (2008 Sequoia) .

Result

Result

Proceed to

DTC B279A is output

A

DTC B279A and other DTCs are output

B

HINT:

If any DTCs other than B279A are output, troubleshoot those DTCs first.

A

3.

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - ECM)

(a) Disconnect the H32 ECU connector.

(b) Disconnect the A27 ECM connector.

(c) Measure the resistance and voltage according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

H32-13 (EFIO) - A27-40 (IMI)

Always

Below 1 Ω

H32-13 (EFIO) or A27-40 (IMI) - Body ground

Always

10 kΩ or higher

Standard Voltage:

Tester Connection

Condition

Specified Condition

H32-13 (EFIO) - Body ground

Always

Below 1 V

A27-40 (IMI) - Body ground

(d) Reconnect the ECU and ECM connector.

OK

4.

INSPECT TRANSPONDER KEY ECU (OUTPUT)

(a) Measure the waveform.

Waveform 1

Terminal No. (Symbol)

Tool Setting

Switch Condition

H32-13 (EFIO) - H32-16 (GND)

10 V/DIV., 500 msec./DIV.

Ignition switch ON

OK:

Waveform is output normally (see illustration).

Result

Result

Proceed to

Waveform is not output normally

A

Waveform is output normally (for 2UZ-FE)

B

Waveform is output normally (for 3UR-FE)

C
A

10.

CHECK TRANSPONDER KEY ECU (POWER SOURCE AND BODY GROUND)

(a) Turn the ignition switch to ON.



(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

H32-1 (+B) - H32-16 (GND)

Ignition switch ON

11 to 14 V
OK