Inspection Procedure

1. Clear the DTCs (see DTC CHECK / CLEAR  ).
2. Check whether DTC B2276 recurs 50 seconds or more after the engine switch is turned on (IG).

   Result 

   RESULT REFERENCE
   
   

   Display (DTC output)	Proceed to
   B2276	A
   No DTC output	B

B: END (SYSTEM IS OK) 

A: Go to Next Step 

1. Disconnect the L12 main body ECU connector.
Fig 1: Identifying L12 Main Body ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value (s) in the table below.

   Standard voltage 

   STANDARD VOLTAGE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   L12-3 (ACCR) - Body ground	When operating the engine switch to crank the engine.	11 to 14 V

OK: Go to step  4

NG: Go to Next Step 

Fig 2: Identifying L12 Main Body ECU And A13 ECM Connectors

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the L12 main body ECU connector.
2. Disconnect the A13 ECM connector.
3. Measure the resistance according to the value (s) in the table below.

   Standard resistance 

   STANDARD RESISTANCE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   L12-3 (ACCR) - A13-19 (ACCR)	Always	Below 1 Ω
   L12-3 (ACCR) or A13-19 (ACCR) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to Next Step 

1. Temporarily replace the main body ECU with a new or normally functioning one.
2. Check whether DTC B2276 recurs by repeating the "CHECK WHETHER DTC OUTPUT RECURS" procedures above.

   OK: No DTC is output. 

NG: GO TO SFI SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

OK: END (MAIN BODY ECU IS FAULTY)