Toyota 2GR-FE Manual page 553

DTC U0101
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.
DTC No.
U0101 No communication from TCM continues
MONITOR STRATEGY
Related DTCs
Required Sensors/Components (Main)
Required Sensors/Components (Sub)
Frequency of Operation
Duration
MIL Operation
Sequence of Operation
TYPICAL ENABLING CONDITIONS
Monitor runs whenever following DTCs are not present
Battery Voltage
Engine switch
Starter
TYPICAL MALFUNCTION THRESHOLDS
Communication signal
TCM
7
CAN-
C56
6
CAN+
C56
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
Lost Communication with TCM
DTC Detection Condition
U0101: Verify communication
ECM
-
Continuous
1.25 seconds
immediate
None
None
10.5 V or more (0.5 second or more)
ON
OFF
Lost communication with TCM
Trouble Area
• Open or short in TCM and ECM circuit
• TCM
• ECM
1
C55
2
C55
ES–397
ES
ECM
CAN-
CAN+
A113695E02