DESCRIPTION
If the engine switch is pressed with the electrical key transmitter sub-assembly in the cabin, the certification ECU (smart key ECU assembly) receives a signal and changes the power source mode.
Related Data List and Active Test Items Problem Symptom | Data List and Active Test |
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Power source mode does not change to on (ACC) but does change to on (IG) | Power Source Control
Starting Control
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WIRING DIAGRAM
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CAUTION / NOTICE / HINT
NOTICE:
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Click here
Click here
HINT:
When the cable is disconnected and reconnected to the negative (-) battery terminal, the power source mode returns to the state it was in before the cable was disconnected.
PROCEDURE
1. | CHECK FOR DTC |
(a) Using the Techstream, check for certification ECU (smart key ECU assembly) DTCs.
Body Electrical > Power Source Control > Trouble Codes Body Electrical > Smart Access > Trouble Codes Body Electrical > Starting Control > Trouble Codes Result | Proceed to |
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DTCs are not output | A |
Smart access system with push-button start (for Start Function) DTCs are output | B |
B | ![]() | GO TO DIAGNOSTIC TROUBLE CODE CHART |
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2. | CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) |
Click here
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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3. | INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC RELAY) |
Click here
NG | ![]() | REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
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4. | CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
Click here
OK | ![]() | USE SIMULATION METHOD TO CHECK |
NG | ![]() | REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
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