Last Modified: 04-05-2023 |
6.11:8.1.0 |
Doc ID: RM100000000VJEH |
Model Year Start: 2016 |
Model: Sienna |
Prod Date Range: [12/2015 - 08/2016] |
Title: NETWORKING: CAN COMMUNICATION SYSTEM: U0100; Lost Communication with ECM / PCM; 2016 MY Sienna [12/2015 - 08/2016] |
DTC
|
U0100
|
Lost Communication with ECM / PCM
|
DESCRIPTION
DTC Code
|
DTC Detection Condition
|
Trouble Area
|
U0100
|
No Communication from the ECM.
|
-
ECM main wire or connector
-
Power source circuit of ECM
-
ECM
|
HINT:
For vehicle with smart key system only.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
-
Turn the ignition switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
-
Turn the ignition switch off before inspecting CAN bus wires for a ground short.
-
After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
-
Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.
-
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
-
Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
-
Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.
PROCEDURE
NOTICE:
After turning the ignition switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work (See page
).
NEXT
|
|
|
2.
|
DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL
|
(a) Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
NOTICE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See page
).
NEXT
|
|
|
3.
|
CHECK FOR OPEN IN CAN BUS WIRE (ECM MAIN WIRE)
|
(a) Disconnect the ECM connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Switch Condition
|
Specified Condition
|
A39-8 (CANP) - A39-9 (CANN)
|
Ignition switch off
|
108 to 132 Ω
|
Text in Illustration
*a
|
Front view of wire harness connector
(to ECM)
|
NG |
|
REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CAN-H, CAN-L)
|
OK
|
|
|
4.
|
CHECK HARNESS AND CONNECTOR (ECM - POWER SOURCE)
|
(a) Connect the cable to the negative (-) battery terminal.
NOTICE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See page
).
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
B1-81 (E1) - Body ground
|
Always
|
Below 1 Ω
|
(d) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
|
Condition
|
Specified Condition
|
B1-41 (+BM) - Body ground
|
Always
|
11 to 14 V
|
Text in Illustration
*a
|
Front view of wire harness connector
(to ECM)
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
|