Toyota Sienna Service Manual: CAN Bus Line
DESCRIPTION
When any DTC for the CAN communication system is output, first measure the resistance between the terminals of the DLC3 to specify the trouble area, and check that there is no short in the CAN main wire, between the main wire, and +B or GND.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
- Turn the ignition switch off before measuring the resistances of CAN bus main 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 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 any doors need to be opened in order to check connectors, open the doors and leave them open.
HINT: Operating the ignition switch, any switches, or any doors triggers related ECU and sensor communication with the CAN. This communication will cause the resistance value to change.
1 CHECK CAN BUS WIRE (MAIN WIRE FOR DISCONNECTION, CAN BUS LINES FOR SHORT CIRCUIT)
- Turn the ignition switch off.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
2 CHECK FOR SHORT TO B+ IN CAN BUS WIRE
- Measure the resistance according to the value(s) in the table below.
Standard resistance
3 CHECK FOR SHORT TO GND IN CAN BUS WIRE
- Measure the resistance according to the value(s) in the table below.
Standard resistance
GO TO HOW TO PROCEED WITH TROUBLESHOOTING
ECM Communication Stop Mode
DESCRIPTION
Detection Item
Symptom
Trouble Area
ECM Communication Stop
Mode
"Engine" is not displayed on the "Communication
Bus Che ...
Open in CAN Main Bus Line
DESCRIPTION
There may be an open circuit in the CAN main bus wire and/or the DLC3 branch
wire when the resistance
between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 69 Ω or higher.
...
Other materials:
Diagnostic trouble code chart
HINT:
If a malfunction code is displayed during the DTC check,
check the circuit indicated by the DTC. For details of each
code, turn to the page for the respective "DTC Code" in the
DTC chart.
DTC chart of ABS:
DTC chart of VSC:
...
Diagnosis system
1. CHECK DLC3
The vehicle's ECU uses ISO 15765-4 for
communication protocol. The terminal arrangement
of the DLC3 complies with SAE J1962 and matches
the ISO 15765-4 format.
NOTICE:
*: Before measuring the resistance, leave the
vehicle as is for at least 1 minute and do not
ope ...
Problem symptoms table
HINT:
Proceed to troubleshooting of each circuit in the table below.
1. HEADLIGHT AND TAIL LIGHT SYSTEM
2. AUTOMATIC LIGHT CONTROL SYSTEM
3. LIGHT AUTO TURN OFF SYSTEM
4. FOG LIGHT SYSTEM
5. TURN SIGNAL AND HAZARD WARNING SYSTEM
6. ILLUMINATED ENTRY SYSTEM
7. OTHE ...
