B279A

ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM: B279A-186: Engine Immobiliser System Communication Line High Fixation
B279A-186 - Engine Immobiliser System Communication Line High Fixation

DESCRIPTION

If the communication line (EFIO-IMI) to the ID code box is stuck on HI output, the hybrid vehicle control ECU outputs this DTC.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CLEAR DTC

(a) Clear the DTC Engine Immobilizer System.

NEXT -- Continue to next step.

2. CHECK FOR DTC

(a) Check for DTC Engine Immobilizer System.

HINT
If any DTCs other than DTC B279A-186 are output, troubleshoot those DTCs first.

Result:





B -- Go to DIAGNOSTIC TROUBLE CODE CHART Engine Immobilizer System
A -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (ID CODE BOX - HYBRID VEHICLE CONTROL ECU)

(a) Disconnect the L32 box connector.





(b) Disconnect the A75 ECU connector.

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

Standard resistance:





Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. CHECK HYBRID VEHICLE CONTROL ECU (INPUT)

(a) Using an oscilloscope, check the waveform.





Waveform 1 (Reference):





OK:

Waveform is output normally (see illustration).

NG -- CHECK ID CODE BOX (POWER SOURCE AND BODY GROUND)

OK -- REPLACE ID CODE BOX Removal

5. CHECK ID CODE BOX (POWER SOURCE AND BODY GROUND)





(a) Turn the power switch ON (IG).

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

Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE HYBRID VEHICLE CONTROL ECU Removal