Last Modified: 11-29-2007 1.6 C
Service Category: Vehicle Interior Section: Theft Deterrent/Keyless Entry
Model Year: 2008 Model: Sequoia Doc ID: RM000001TCN007X
Title: THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM: DESCRIPTION (2008 Sequoia)

DTC

B2784

Antenna Coil Open / Short

DESCRIPTION

The antenna coil receives key code signals from the transponder chip in the key grip. The coil is built into the transponder key amplifier, which amplifies the key code signals and outputs the signals to the transponder key ECU.

This DTC is output when there is an open or short malfunction in the antenna coil.

DTC Code

DTC Detection Condition

Trouble Area

B2784
  • When performing immobiliser set/unset, the antenna coil circuit is opened or shorted for 5 seconds.
  • When performing immobiliser set/unset, the ignition switch is not connected for 5 seconds.
  • Harness or connector
  • Transponder key ECU
  • Transponder key amplifier

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

When the transponder key ECU is replaced, reregister the ECU - ECM communication ID THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM: REGISTRATION (2008 Sequoia)+ .

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)


(a) Disconnect the H32 ECU connector.

(b) Disconnect the H27 amplifier connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

H32-14 (VC5) - H27-1 (VC5)

Always

Below 1 Ω

H32-15 (CODE) - H27-4 (CODE)

H32-4 (TXCT) - H27-5 (TXCT)

H32-5 (AGND) - H27-7 (AGND)

H32-14 (VC5) or H27-1 (VC5) - Body ground

Always

10 kΩ or higher

H32-15 (CODE) or H27-4 (CODE) - Body ground

H32-4 (TXCT) or H27-5 (TXCT) - Body ground

H32-5 (AGND) or H27-7 (AGND) - Body ground

(d) Reconnect the ECU connector.

(e) Reconnect the amplifier connector.

OK

2.

INSPECT TRANSPONDER KEY ECU (VC5,AGND)


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

Standard Voltage:

Tester Connection

Condition

Specified Condition

H32-14 (VC5) - Body ground

No key is in ignition key cylinder

Below 1 V

H32-14 (VC5) - Body ground

Key is in ignition key cylinder

4.6 to 5.4 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

H32-5 (AGND) - Body ground

Always

Below 1 Ω
OK

3.

REPLACE TRANSPONDER KEY AMPLIFIER

(a) Temporarily replace the transponder key amplifier with a new or normally functioning one THEFT DETERRENT / KEYLESS ENTRY: TRANSPONDER KEY AMPLIFIER: REMOVAL (2008 Sequoia) .

NEXT

4.

CLEAR DTC

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

NEXT

5.

CHECK FOR DTC

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

OK:

DTC B2784 is not output.

OK