Theft Deterrent / Keyless Entry

Engine Immobiliser System Malfunction (B2799)

~3min read
DESCRIPTION

This DTC is stored when one of the following occurs: 1) the ECM detects errors in its own communications with the transponder key ECU assembly; 2) the ECM detects errors in the communication lines; or 3) the ECU communication ID between the transponder key ECU assembly and ECM is different and an engine start is attempted.

Before troubleshooting for this DTC, make sure that no transponder key ECU assembly DTCs are present. If present, troubleshoot the transponder key ECU assembly DTCs first.

DTC No.

DTC Detection Condition

Trouble Area

B2799

One of the following conditions is met:

  • Error in communication between ECM and transponder key ECU assembly.
  • Error in communication lines.
  • Communication ID is different during communication with transponder key ECU assembly.
  • Wire harness or connector
  • ECM
  • Transponder key ECU assembly
WIRING DIAGRAM
CAUTION / NOTICE / HINT

NOTICE:

  • If the transponder key ECU assembly is replaced, register the key and ECU communication ID (See page ).
  • If the ECM is replaced, register the ECU communication ID (See page ).
PROCEDURE
  1. CHECK DTC OUTPUT

(a) Clear the DTCs (See page ).


(b) Recheck for DTCs (See page ).


OK:

DTC B2799 is not output.


OK

USE SIMULATION METHOD TO CHECK

NG
  1. RE-REGISTER ECU COMMUNICATION ID

(a) Re-register the ECU communication ID (See page ).


NEXT
  1. CHECK DTC OUTPUT

(a) Clear the DTCs (See page ).


(b) Recheck for DTCs (See page ).


OK:

DTC B2799 is not output.


OK

END (ECU COMMUNICATION ID WAS NOT REGISTERED CORRECTLY)

NG
  1. CHECK CONNECTION OF CONNECTOR

(a) Turn the ignition switch off.

(b) Check that the connectors are properly connected to the ECM and transponder key ECU assembly.

OK:

Connectors are properly connected.


NG

CONNECT CONNECTORS PROPERLY

OK
  1. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - ECM)

(a) Disconnect the transponder key ECU assembly connector.

(b) Disconnect the ECM connector.

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

Standard Resistance:

for 2GR-FE

Tester Connection

Condition

Specified Condition

D22-12 (EFII) - A41-29 (IMO)

Always

Below 1 Ω

D22-13 (EFIO) - A41-40 (IMI)

Always

Below 1 Ω

D22-12 (EFII) - Body ground

Always

10 kΩ or higher

D22-13 (EFIO) - Body ground

Always

10 kΩ or higher

A41-29 (IMO) - Body ground

Always

10 kΩ or higher

A41-40 (IMI) - Body ground

Always

10 kΩ or higher

for 1AR-FE

Tester Connection

Condition

Specified Condition

D22-12 (EFII) - A49-10 (IMO)

Always

Below 1 Ω

D22-13 (EFIO) - A49-11 (IMI)

Always

Below 1 Ω

D22-12 (EFII) - Body ground

Always

10 kΩ or higher

D22-13 (EFIO) - Body ground

Always

10 kΩ or higher

A49-10 (IMO) - Body ground

Always

10 kΩ or higher

A49-11 (IMI) - Body ground

Always

10 kΩ or higher

Text in Illustration

*1

Front view of wire harness connector

(to Transponder Key ECU Assembly)

*2

Front view of wire harness connector

(to ECM)

*3

for 2GR-FE

*4

for 1AR-FE


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
  1. REPLACE ECM

(a) Replace the ECM (See page for 2GR-FE,
for 1AR-FE).


NEXT
  1. REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID (See page ).


NEXT
  1. CHECK DTC OUTPUT

(a) Clear the DTCs (See page ).


(b) Recheck for DTCs (See page ).


OK:

DTC B2799 is not output.


OK

END (ECM WAS DEFECTIVE)


NG

REPLACE TRANSPONDER KEY ECU ASSEMBLY

Test yourself

A quick Toyota Venza quiz: every answer comes with an explanation and a link to the manual page.