Can Communication System (For Sedan) Ecm Communication Stop Mode
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
CHECK CAN BUS LINE FOR DISCONNECTION (ECM MAIN WIRE)
INSPECT ECM POWER SOURCE CIRCUIT
CAN COMMUNICATION SYSTEM (for Sedan) - ECM Communication Stop Mode |
DESCRIPTION
Detection Item
| Symptom
| Trouble Area
|
ECM Communication Stop Mode
| - "Engine" not displayed on "Communication Bus Check" screen of Techstream
- Applies to "ECM Communication Stop Mode" in "DTC combination table"
| - Power source circuit of ECM
- ECM main wire or connector
- ECM
|
WIRING DIAGRAM
INSPECTION PROCEDURE
- NOTICE:
- Turn the ignition switch OFF before measuring the resistances of the CAN main wire and the CAN branch wire.
- After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
- 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 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 switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.
| 1.CHECK CAN BUS LINE FOR DISCONNECTION (ECM MAIN WIRE) |
Turn the ignition switch off.
Disconnect the A21 ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection
| Switch Condition
| Specified Condition
|
A21-41 (CANH) - A21-49 (CANL)
| Ignition switch off
| 108 to 132 Ω
|
Text in Illustration*1
| Front view of wire harness connector
(to ECM)
|
| | REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (CAN-H, CANL) |
|
|
| 2.INSPECT ECM POWER SOURCE CIRCUIT |
Inspect the power source circuit (YARIS_NCP93 RM000001DN805UX.html).
| | GO TO POWER SOURCE CIRCUIT |
|
|
