2Gr-Fe Starting. Dtc B2278 Engine Switch Circuit Malfunction

Engine. Camry. Acv40 Gsv40

2Gr-Fe Starting. Camry. Acv40 Gsv40

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (START SWITCH)

CHECK ENGINE SWITCH CONDITION

INSPECT ENGINE SWITCH

CHECK HARNESS AND CONNECTOR (ENGINE SWITCH - MAIN BODY ECU AND BODY GROUND)

DTC B2278 Engine Switch Circuit Malfunction

DESCRIPTION

This DTC is output 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.

HINT:

When the main body ECU is replaced with a new one and the negative (-) battery terminal is connected, the power source mode becomes the IG-ON mode. When the battery is removed and reinstalled, the power source mode that was selected when the battery was removed is restored.

After the main body ECU is replaced, perform the registration procedures for the engine immobiliser system.

DTC No.	DTC Detection Condition	Trouble Area
B2278	Communication is abnormal between the main body ECU and engine switch or the engine switch is defective	Engine switch Main body ECU Wire harness or connector

WIRING DIAGRAM

Camry. Acv40 Gsv40.2Gr-Fe Starting.Starting System.
Dtc
B2278 Engine Switch Circuit Malfunction

INSPECTION PROCEDURE

1.READ VALUE USING INTELLIGENT TESTER (START SWITCH)

Connect the intelligent tester to the DLC3.

Check the Data List for proper functioning of the start switch.

HINT:

When using the intelligent tester with the engine switch off, turn on and off any of the door courtesy light switches repeatedly at 1.5 second intervals or less until communication between the tester and vehicle starts.

Body:
Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
St SW 1	Start Switch 1/ON or OFF	ON: Engine switch on (IG) OFF: Engine switch off	-
St SW 2	Start Switch 2/ON or OFF	ON: Engine switch on (IG) OFF: Engine switch off	-

OK:: ON (engine switch on (IG)) and OFF (engine switch off) appear on the screen.

Go to step 3

OK

2.CHECK ENGINE SWITCH CONDITION

Check the power source mode change.
1. When the key is inside the vehicle and the shift lever is in the P position, check that pressing the engine switch causes the power source mode to change as follows:
  OK:
  off → on (ACC) → on (IG) → off
  HINT:
  1. If power mode does not change to ON (IG and ACC) (CAMRY_ACV40 RM0000020S906WX.html).
  2. If power mode does not change to ON (IG) (CAMRY_ACV40 RM0000020SA027X.html).
  3. If power mode does not change to ON (ACC) (CAMRY_ACV40 RM0000020SB027X.html).

GO TO OTHER PROBLEM

USE SIMULATION METHOD TO CHECK (CAMRY_ACV40 RM000000UZ104DX.html)

3.INSPECT ENGINE SWITCH

Remove the engine switch (CAMRY_ACV40 RM0000026WR01JX.html).

Disconnect the 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

HINT:

This switch is a momentary type switch.

REPLACE ENGINE SWITCH (CAMRY_ACV40 RM0000026WR01JX.html)

OK

4.CHECK HARNESS AND CONNECTOR (ENGINE SWITCH - MAIN BODY ECU AND BODY GROUND)

Disconnect the E7 ECU connector.

Disconnect the E52 switch connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
E52-7 (SS1) - E7-17 (SSW1)	Always	Below 1 Ω
E52-2 (SS2) - E7-16 (SSW2)	Always	Below 1 Ω
E52-5 (GND) - Body ground	Always	Below 1 Ω
E52-7 (SS1) or E7-17 (SSW1) - Body ground	Always	10 kΩ or higher
E52-2 (SS2) or E7-16 (SSW2) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE MAIN BODY ECU