DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
READ VALUE USING INTELLIGENT TESTER (START SWITCH 1, 2)
CHECK WHETHER DTC OUTPUT RECURS
INSPECT ENGINE SWITCH
CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ENGINE SWITCH AND BODY GROUND)
DTC B2278 Engine Switch Circuit Malfunction
DESCRIPTION
This DTC is stored when: 1) a malfunction is detected between the main body ECU and the engine switch; or 2) either of the switches inside the engine switch is malfunctioning.
| DTC Code | Detection Condition | Trouble Area |
| B2278 | Communication is abnormal between the main body ECU and engine switch or the engine switch is defective. | Main body ECU
Engine switch
Harness or connector
|
WIRING DIAGRAM
INSPECTION PROCEDURE
| 1.READ VALUE USING INTELLIGENT TESTER (START SWITCH 1, 2) |
Use the Data List to check if the engine switch is functioning properly.
Main Body| Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
| Start Switch 1 | Start Switch 1/ON or OFF | ON: Engine switch on (IG)
OFF: Engine switch off | - |
| Start Switch 2 | Start Switch 2/ON or OFF | ON: Engine switch on (IG)
OFF: Engine switch off | - |
- OK:
- When the engine switch is turned on (IG), ON is displayed on the intelligent tester.
| 2.CHECK WHETHER DTC OUTPUT RECURS |
Turn the engine switch on (IG), and check whether DTC B2278 is output.
Result| Result | Proceed to |
| No DTC output | A |
| DTC B2278 output | B |
| A | |
| |
| USE SIMULATION METHOD TO CHECK ()
|
|
Disconnect the E18 engine switch connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
| Tester Connection | Switch Condition | Specified Condition |
| 7 (SS1) - 5 (GND) | Pushed | Below 1 Ω |
| 2 (SS2) - 5 (GND) | Pushed | Below 1 Ω |
| 7 (SS1) - 5 (GND) | Not pushed | 10 kΩ or higher |
| 2 (SS2) - 5 (GND) | Not pushed | 10 kΩ or higher |
Result| Result | Proceed to |
| Within specified range | A |
| Outside specified range (for 1GR-FE) | B |
| Outside specified range (for 1UR-FE) | C |
| Outside specified range (for 3UR-FE) | D |
| Outside specified range (for 1VD-FTV) | E |
| 4.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ENGINE SWITCH AND BODY GROUND) |
Disconnect the E1 main body ECU connector.
Disconnect the E18 engine switch connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
| Tester Connection | Condition | Specified Condition |
| E1-17 (SSW1) - E18-7 (SS1) | Always | Below 1 Ω |
| E1-16 (SSW2) - E18-2 (SS2) | Always | Below 1 Ω |
| E18-5 (GND) - Body ground | Always | Below 1 Ω |
| E1-17 (SSW1) or E18-7 (SS1) - Body ground | Always | 10 kΩ or higher |
| E1-16 (SSW2) or E18-2 (SS2) - Body ground | Always | 10 kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
