DTC B2785: Communication Malfunction between ECUs Connected by LIN: Procedure

Fig 1: Identifying Terminals Of E84 And E77 ECU Connectors

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1. Disconnect the E84 and E77 ECU connectors.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   E84-10 (LIN) - E77-5 (LIN)	Always	Below 1 Ω
   E84-10 (LIN) - Body ground	Always	10 kΩ or higher

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   E84-10 (LIN) - Body ground	Always	Below 1 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Clear the DTC. Refer to DTC CHECK / CLEAR .
2. Reconnect the E84 ECU connector.
3. Recheck for DTCs.

   OK

   B2785 does not reoccur.

NG → See step   5 

OK: Go to next step 

1. Clear the DTC. Refer to DTC CHECK / CLEAR .
2. Reconnect the E77 ECU connector.
3. Disconnect the 1D ECU connector.
4. Recheck for DTCs.

   OK

   B2785 does not reoccur.

NG → See step   7 

OK: Go to next step 

1. Clear the DTC. Refer to DTC CHECK / CLEAR .
2. Reconnect the 1D ECU connector.
3. Disconnect the E79 ECU connector.
4. Recheck for DTCs.

   OK

   B2785 does not reoccur.

NG → See step   9 

OK → See step   11 

1. Temporarily replace the steering lock ECU with a new one. Refer to REMOVAL .
   NOTE:

   When replacing the steering lock ECU, registration must be performed according to the "Registration" procedures. Refer to REGISTRATION .

2. Clear the DTC. Refer to DTC CHECK / CLEAR .

NEXT: Go to next step 

1. Recheck for DTCs.

   OK

   B2785 does not reoccur.

NG → See step   11 

OK → END (STEERING LOCK ECU IS DEFECTIVE) 

1. Temporarily replace the main body ECU (instrument panel junction block) with a new or normally functioning one.
2. Clear the DTC. Refer to DTC CHECK / CLEAR .

NEXT: Go to next step 

1. Recheck for DTCs.

   OK

   B2785 does not reoccur.

NG → See step   11 

OK → END (MAIN BODY ECU IS DEFECTIVE) 

1. Temporarily replace the ID code box with a new one. Refer to REMOVAL .
   NOTE:

   When replacing the ID code box, registration must be performed according to the "Registration" procedures. Refer to REGISTRATION .

2. Clear the DTC. Refer to DTC CHECK / CLEAR .

NEXT: Go to next step 

1. Recheck for DTCs. Refer to DTC CHECK / CLEAR .

   OK

   B2785 does not reoccur.

NG → See step   11 

OK → END (ID CODE BOX IS DEFECTIVE)