Smart Key System (for Start Function)
THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): U0100: Lost Communication with ECM / PCM
U0100 - Lost Communication with ECM / PCM
DESCRIPTION
This DTC is stored when a malfunction in the CAN communication between the power source control ECU and ECM is detected.
HINT
* When the power source control ECU is replaced with a new one and the cable is connected to the negative (-) battery terminal, the power source mode changes to on (IG).
* When the battery cable is disconnected and reconnected, the power source returns to the mode it was in before the battery cable was disconnected.
* *: Only output while a malfunction is present and the engine switch is on (IG)
Vehicle Condition and Fail-safe Function when Malfunction Detected
INSPECTION PROCEDURE
NOTICE:
* When using the Techstream with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Key / Trouble Codes.
* The smart key system uses multiplex communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting How to Proceed With Troubleshooting.
* Inspect the fuses of circuits related to this system before performing the following inspection procedure.
* After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.
HINT
Related Data List and Active Test Items
PROCEDURE
1. CHECK FOR DTC
(a) Record any output DTCs Smart Key System (for Start Function).
NOTICE:
* When using the Techstream with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Key / Trouble Codes.
* The smart key system uses multiplex communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting How to Proceed With Troubleshooting.
NEXT -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting