DESCRIPTION
This DTC is stored when the SSW1 contact signal and SSW2 contact signal, which are detected when the engine switch is operated, do not match.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Note |
---|---|---|---|---|
B2278 | Engine/Power Switch Malfunction | When the engine switch is operated, the SSW1 contact signal and SSW2 contact signal do not match (1-trip detection logic*). |
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Vehicle Condition when Malfunction Detected | Fail-safe Function when Malfunction Detected |
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If either the SSW1 contact signal or SSW2 contact signal is stuck on, the power source mode cannot be changed by pressing the engine switch. If either the SSW1 contact signal or SSW2 contact signal is stuck off, emergency stop by pressing and holding the engine switch for 2 seconds or more cannot be operated. | - |
DTC No. | Data List and Active Test |
---|---|
B2278 | Power Source Control
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WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
Click here
HINT:
When the cable is disconnected and reconnected to the negative (-) battery terminal, the power source mode returns to the state it was in before the cable was disconnected.
PROCEDURE
1. | READ VALUE USING TECHSTREAM (START SWITCH1, START SWITCH2) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Power Source Control / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Power Source Control > Data List Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
---|---|---|---|---|
Start Switch1 | Engine switch 1 status | OFF or ON | OFF: Engine switch not pressed ON: Engine switch pressed |
|
Start Switch2 | Engine switch 2 status | OFF or ON | OFF: Engine switch not pressed ON: Engine switch pressed |
|
Tester Display |
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Start Switch1 |
Start Switch2 |
OK:
The Techstream display changes correctly in response to the engine switch operation.
NG | ![]() | GO TO STEP 3 |
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2. | READ VALUE USING TECHSTREAM (START SWITCH1, START SWITCH2) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Power Source Control / Data List.
(e) According to the display on the Techstream, read the Data List while wiggling the wire harness.
Body Electrical > Power Source Control > Data List Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
---|---|---|---|---|
Start Switch1 | Engine switch 1 status | OFF or ON | OFF: Engine switch not pressed ON: Engine switch pressed |
|
Start Switch2 | Engine switch 2 status | OFF or ON | OFF: Engine switch not pressed ON: Engine switch pressed |
|
Tester Display |
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Start Switch1 |
Start Switch2 |
OK:
The Techstream display changes correctly in response to the engine switch operation.
OK | ![]() | USE SIMULATION METHOD TO CHECK |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
3. | CHECK HARNESS AND CONNECTOR (POWER SOURCE) |
Click here
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
4. | CHECK HARNESS AND CONNECTOR (GROUND) |
Click here
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
5. | CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE SWITCH) |
(a) Disconnect the J14 engine switch connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J41-23 (SSW1) - J14-5 (SS1) | Always | Below 1 Ω |
J41-21 (SSW2) - J14-1 (SS2) | Always | Below 1 Ω |
J41-11 (AGND) - J14-6 (AGND) | Always | Below 1 Ω |
J41-23 (SSW1) or J14-5 (SS1) - Body ground | Always | 10 kΩ or higher |
J41-21 (SSW2) or J14-1 (SS2) - Body ground | Always | 10 kΩ or higher |
J41-11 (AGND) or J14-6 (AGND) - Body ground | Always | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
6. | INSPECT ENGINE SWITCH |
(a) Remove the engine switch.
Click here
(b) Inspect the engine switch.
Click here
OK | ![]() | REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
NG | ![]() | REPLACE ENGINE SWITCH |
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