Automatic Transmission System

A750E AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM (for 2UZ-FE): U0100: Lost Communication with ECM / PCM "A"

DTC U0100 - Lost Communication with ECM / PCM "A"

DESCRIPTION

The engine control unit and the transmission control unit are located inside the ECM. The engine control unit intercommunicates with the transmission control unit with the Controller Area Network (CAN). If there is a problem in this intercommunication, the ECM sets a DTC.






MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





INSPECTION PROCEDURE

PROCEDURE

1. CHECK DTC OUTPUT (IN ADDITION TO DTC P0100)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / ECT / Trouble Codes.
(e) Read the DTCs using the Techstream.

Result





HINT: If any other codes besides U0100 are output, perform troubleshooting for those DTCs first.

B -- GO TO DTC CHART
A -- Continue to next step.
2. REPLACE ECM
(a) Replace the ECM Removal.
NEXT -- Continue to next step.
3. CHECK IF DTC RECURS
(a) Clear the DTC DTC Check / Clear.
(b) Start the engine.
(c) Read the DTCs using the Techstream.

Result





B -- GO TO DTC CHART
A -- END