DTC B279A: Theft Deterrent System Communication Line High Fixation (TO 12/2010): Procedure

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Recheck for DTCs.

   HINT: 

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

   Result

   Result	Proceed to
   DTC B279A is output	A
   DTC B279A and other DTCs are output	B

B → See step   8 

A: Go to next step 

1. Disconnect the D29 ID code box and A55 ECM connectors.
   Fig 1: Identifying D29 ID Code Box And A55 ECM Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Resistance

   Tester Connection	Condition	Specified Condition
   D29-6 (EFIO) - A55-11 (IMI)	Always	Below 1 Ω
   D29-6 (EFIO) - Body ground	Always	10 kΩ or higher

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

   Voltage

   Tester Connection	Condition	Specified Condition
   D29-6 (EFIO) - Body ground	Always	Below 1 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Reconnect the D29 ID code box and A55 ECM connectors.
2. Using an oscilloscope, check the waveform.
   Fig 2: Identifying Waveform Graph

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Waveform (Reference)

   Item	Content
   Terminal No. (Symbol)	D29-6 (EFIO) - D29-8 (GND)
   Tool Setting	10 V/DIV., 100 msec./DIV.
   Condition	Engine switch on (IG)

   OK

   Normal waveform is output (see  Fig.31 illustration).

NG → See step   4 

OK → See step   9 

1. Replace the ID code box. Refer to REMOVAL .

NEXT: Go to next step 

1. Register the ECU code. Refer to REGISTRATION .

NEXT: Go to next step 

1. Register the ECU communication ID. Refer to REGISTRATION .

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Recheck for DTCs.

   OK

   DTC B279A is not output.

NG → See step   9 

OK → END (ID CODE BOX WAS DEFECTIVE)