DTC B2785: Communication Malfunction between ECUs Connected by LIN [09/2022 - ]: Procedure
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- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ID CODE BOX (IMMOBILISER CODE ECU))
- Disconnect the G47 certification ECU (smart key ECU assembly) connector.
- Disconnect the G52 ID code box (immobiliser code ECU) connector.
- Measure the resistance according to the value(s) in the table below.NOTE:
Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the power switch from on (IG) to off and wait for 180 seconds or more without operating any switches.
Standard Resistance
Tester Connection Condition Specified Condition G47-13 (LIN) - G52-2 (LIN1) Power switch off Below 1 Ω G47-13 (LIN) or G52-2 (LIN1) - Body ground Power switch off 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 2
- CHECK FOR DTC
- Connect the G47 certification ECU (smart key ECU assembly) connector.
- Clear the DTCs.
Body Electrical > Smart Access > Clear DTCs
- Recheck for DTCs.
Body Electrical > Smart Access > Trouble Codes
Result
Result Proceed to DTC B2785 is output A DTC B2785 is not output B
Result:
A
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL [09/2022 - ]
Result:
B
REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to REMOVAL [09/2022 - ]