DTC U0100-87: Lost Communication with ECM/PCM "A" Missing Message [10/2022 - ]: Description
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The engine control unit and transmission control unit are located inside the ECM. The engine control unit intercommunicates with the transmission control unit using CAN communication.
If there is a problem in this intercommunication, the ECM stores this DTC.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | DTC Output from | Priority | Note |
|---|---|---|---|---|---|---|---|
| U0100-87 | Lost Communication with ECM/PCM "A" Missing Message | While the ignition switch is ON, there is no communication between the engine control unit and transmission control unit for 1.25 seconds or more (1-trip detection logic). | ECM | Comes on | Transmission | B | SAE Code: U0100 |