DESCRIPTION
If the certification ECU (smart key ECU assembly) detects a communication error with an ECU connected to the certification bus lines for 7 sedonds or more, DTC B2785 will be stored.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
---|---|---|---|
B2785 | Communication Malfunction between ECUs Connected by LIN |
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WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
Click here
PROCEDURE
1. | CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - EACH ECU) |
(a) Disconnect the J41 certification ECU (smart key ECU assembly) connector.
(b) Disconnect the L1 steering lock ECU (steering lock actuator or upper bracket assembly) connector.
(c) Disconnect the J36 ID code box (immobiliser code ECU) connector.
(d) Measure the resistance according to the value(s) in the table below.
NOTICE:
Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the engine switch from on (IG) to off and wait for 180 seconds or more without operating any switches.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J41-13 (LIN) - J36-2 (LIN1) | Engine switch off | Below 1 Ω |
J41-13 (LIN) - L1-5 (LIN) | Engine switch off | Below 1 Ω |
J41-13 (LIN), L1-5 (LIN) or J36-2 (LIN1) - Body ground | Engine switch off | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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2. | CHECK FOR DTC (STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY)) |
(a) Reconnect the J41 certification ECU (smart key ECU assembly) connector.
(b) Reconnect the J36 ID code box (immobiliser code ECU) connector.
(c) Clear the DTCs.
Click here
(d) Recheck for DTCs.
Body Electrical > Smart Access > Trouble Codes Result | Proceed to |
---|---|
DTC B2785 is output | A |
DTC B2785 is not output | B |
B | ![]() | REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY) |
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3. | CHECK FOR DTC (ID CODE BOX (IMMOBILISER CODE ECU)) |
(a) Reconnect the L1 steering lock ECU (steering lock actuator or upper bracket assembly) connector.
(b) Disconnect the J36 ID code box (immobiliser code ECU) connector.
(c) Clear the DTCs.
Click here
(d) Recheck for DTCs.
Body Electrical > Smart Access > Trouble Codes Result | Proceed to |
---|---|
DTC B2785 is output | A |
DTC B2785 is not output | B |
A | ![]() | REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
B | ![]() | REPLACE ID CODE BOX (IMMOBILISER CODE ECU) |
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