U0101

2UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: U0101: Lost Communication with TCM

DTC U0101 - Lost Communication with TCM

DESCRIPTION

The Transmission Control Module (TCM) and ECM perform 2-way communications with each other via the Controller Area Network (CAN). The TCM sends signals to the ECM concerning required engine rpm, required engine torques, warning indicators in the combination meter, DTCs and other data. The ECM sends signals to the TCM concerning engine rpm, opening angles of the throttle valve, temperature of intake air, temperature of engine coolant, engine torques and other data. If the TCM cannot communicate with the ECM, the TCM will conclude that there is a malfunction in the CAN system, illuminate the MIL and set a DTC.





MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





INSPECTION PROCEDURE

PROCEDURE

1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC U0101)
(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 / Engine and ECT / Trouble Codes.
(e) Read the DTCs.

Result





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) Connect the Techstream to the DLC3.
(b) Clear the DTC (DTC Check / Clear).
(c) Start the engine.
(d) Read the DTCs.

Result





B -- GO TO DTC CHART
A -- END