Monitor Description

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The engine control unit and the transmission control unit are located inside the ECM. The engine control unit intercommunicates with the transmission control via CAN communication.

If there is a problem in this communication, the ECM stores this DTC.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
U0101-87	Lost Communication with TCM Missing Message	All of the following conditions are met for 1.25 seconds or more (1 trip detection logic): Ignition switch ON Battery voltage is 10 V or higher No communication between engine control unit and transmission control unit	ECM	Comes on	DTC stored	SAE Code: U0101 DTC for Mexico Models: Applies