DESCRIPTION
This DTC is stored when the engine switch power source supply line is open or shorted.
DTC Code |
DTC Detection Condition |
Trouble Area |
---|---|---|
B278A |
The engine switch power source supply line is open or shorted. |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Before replacing the certification ECU, refer to Registration (See page ).
PROCEDURE
1. |
CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ENGINE SWITCH) |
(a) Disconnect the F79 ECU connector.
(b) Disconnect the F71 switch connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
F79-28 (VC5) - F71-14 (VC5) |
Always |
Below 1 Ω |
F79-36 (AGND) - F71-8 (AGND) |
||
F79-28 (VC5) or F71-14 (VC5) - Body ground |
Always |
10 kΩ or higher |
F79-36 (AGND) or F71-8 (AGND) - Body ground |
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
2. |
CHECK CERTIFICATION ECU |
(a) Using an oscilloscope, check the waveform. Measurement Condition
OK: Waveform is output normally (refer to illustration). Text in Illustration
|
|
OK |
REPLACE ENGINE SWITCH |
NG |
REPLACE CERTIFICATION ECU |
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART
HINT:
If a trouble code is output during the DTC check, inspect the trouble areas listed
for that code. For details of the code, refer to the "See page" below.
Lighting System
DTC Code
Detecti ...
Entry Interior Alarm does not Sound
DESCRIPTION
The smart key system uses the combination meter buzzer to perform various vehicle
interior warnings. When the conditions of each warning are met, the certification
ECU sends a buzzer signal to the combination meter assembly, and the combinatio ...