DESCRIPTION
The Certification ECU monitors the LIN communication bus between the components related to the certification intermittently. DTC B2785 is output when a malfunction in the LIN communication bus between the components related to the certification is detected continuously 3 times.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| B2785 | Certification ECU detects malfunction in LIN communication bus between components related to certification continuously 3 times |
|
WIRING DIAGRAM
INSPECTION PROCEDURE
Note
When using the intelligent tester with the engine switch off to troubleshoot:
Connect the intelligent tester to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the tester and vehicle begins.
Tech Tips
When DTC B2785 and B2287 are output simultaneously, perform the troubleshooting for DTC B2785 first.
PROCEDURE
CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - MAIN BODY ECU)
Disconnect the L15 and DA ECU connectors.
Measure the resistance and voltage according to the value(s) in the table below.
| Standard resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Standard voltage | ||||||
|---|---|---|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK FOR DTC
Clear the DTC Click here.
Reconnect the L15 ECU connector.
Recheck for DTCs.
| Result | Proceed to |
|---|---|
| DTC B2785 is output | A |
| DTC B2785 is not output | B |
| B |
|
REPLACE MAIN BODY ECU Click here |
| A |
|
CHECK FOR DTC
Clear the DTC Click here.
Disconnect the DA ECU connector.
Disconnect the L33 ECU connector.
Recheck for DTCs.
| Result | Proceed to |
|---|---|
| DTC B2785 is output | A |
| DTC B2785 is not output | B |
| B |
|
REPLACE STEERING LOCK ECU Click here |
| A |
|
CHECK FOR DTC
Clear the DTC Click here.
Reconnect the L33 ECU connector.
Disconnect the L32 box connector.
Recheck for DTCs.
| Result | Proceed to |
|---|---|
| DTC B2785 is output | A |
| DTC B2785 is not output | B |
| B |
|
REPLACE ID CODE BOX Click here |
| A |
|
REPLACE CERTIFICATION ECU
REPLACE MAIN BODY ECU
Temporarily replace the main body ECU with a new or normally functioning one.
Clear the DTC Click here.
| NEXT |
|
CHECK FOR DTC
Recheck for DTCs.
| Result | Proceed to |
|---|---|
| DTC B2785 is not output | A |
| DTC B2785 is output | B |
| B |
|
REPLACE CERTIFICATION ECU |
| A |
|
END (MAIN BODY ECU IS DEFECTIVE)
REPLACE STEERING LOCK ECU
Temporarily replace the steering lock ECU with a new or normally functioning one Click here.
Clear the DTC Click here.
| NEXT |
|
CHECK FOR DTC
Recheck for DTCs.
| Result | Proceed to |
|---|---|
| DTC B2785 is not output | A |
| DTC B2785 is output | B |
| B |
|
REPLACE CERTIFICATION ECU |
| A |
|
END (STEERING LOCK ECU IS DEFECTIVE)
REPLACE ID CODE BOX
Temporarily replace the ID code box with a new or normally functioning one.
Clear the DTC Click here.
| NEXT |
|
CHECK FOR DTC
Recheck for DTCs Click here.
| Result | Proceed to |
|---|---|
| DTC B2785 is not output | A |
| DTC B2785 is output | B |
| B |
|
REPLACE CERTIFICATION ECU |
| A |
|
END (ID CODE BOX IS DEFECTIVE)