Can Communication System Ecm Communication Stop Mode
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
CHECK FOR OPEN IN CAN NO. 1 BUS MAIN WIRE (ECM MAIN WIRE)
CHECK WIRE HARNESS (POWER SOURCE CIRCUIT)
CAN COMMUNICATION SYSTEM - ECM Communication Stop Mode |
DESCRIPTION
Detection Item
| Symptom
| Trouble Area
|
ECM Communication Stop Mode
| - "Engine" is not displayed on the "CAN Bus Check" screen of the Techstream
- Applies to "ECM Communication Stop Mode" in "DTC Combination Table"
| - Power source circuit of ECM
- ECM
|
WIRING DIAGRAM
INSPECTION PROCEDURE
- NOTICE:
- Turn the ignition switch off before measuring the resistance between main CAN bus wires and CAN Bus branch wires.
- 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 the connectors, open the doors and leave them open.
- 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.
1.CHECK FOR OPEN IN CAN NO. 1 BUS MAIN WIRE (ECM MAIN WIRE) |
Turn the ignition switch off.
Disconnect the ECM connector.
Text in Illustration*a
| Front view of wire harness connector (to ECM)
|
*b
| for 2AZ-FE
|
*c
| for 2ZR-FE
|
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection
| Switch Condition
| Specified Condition
|
A50-41 (CANH) - A50-49 (CANL)*1
| Ignition switch off
| 108 to 132 Ω
|
A50-8 (CANH) - A50-9 (CANL)*2
| Ignition switch off
| 108 to 132 Ω
|
*1: for 2AZ-FE
*2: for 2ZR-FE
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
2.CHECK WIRE HARNESS (POWER SOURCE CIRCUIT) |
Check the ECM power source circuit (2ZR-FE: COROLLA_ZRE142 RM0000027690AZX.html, 2AZ-FE: COROLLA_ZRE142 RM000001F7102ZX.html).
- Result:
Result
| Proceed to
|
OK (2ZR-FE)
| A
|
OK (2AZ-FE)
| B
|
NG
| C
|
| |
|
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|