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 |
Air Conditioning Compressor Magnetic Clutch Circuit
DESCRIPTION
When the air conditioning amplifier assembly is turned on, a magnet clutch assembly
signal is sent from the MGC terminal of the air conditioning amplifier assembly.
Then, the A/C COMP relay turns on to operate the magnet clutch assembly.
WIRI ...
Power Mirror Control System
Precaution
PRECAUTION
1. IGNITION SWITCH EXPRESSION
HINT:
The type of ignition switch used on this model differs according to the specifications
of the vehicle. The expressions listed in the table below are used in this section.
Expression
...