Toyota Sienna Service Manual: How to proceed with troubleshooting
NOTICE: DTCs for the CAN communication system are as follows: U0073, U0100, U0122, U0123, U0124, U0126 and U1101.
HINT: If U0235 or U1102 is output alone, the CAN communication is normal
1 CHECK AND CLEAR DTCS
HINT:
- CAN communication DTCs are output when there is an open or short in any of the communication wires. Any problems with the power source of a corresponding ECU or sensor, or problems in the ECU or the sensor itself also cause these DTCs to be output.
- If a CAN communication wire connector is disconnected with the ignition switch on (IG), the ECUs of the corresponding system and related systems record a DTC.
2 CHECK FOR INSTALLED SYSTEMS (ECUS & SENSORS) THAT ADOPT CAN COMMUNICATION)
- Check which of the following is adopted: brake control system and dynamic laser cruise control system
3 CHECK WITH INTELLIGENT TESTER
- Using the intelligent tester, display the "Communication Bus Check" screen (See page CA-17).
- Observe the screen for approximately 1 minute to check the ECUs and sensors displayed on the screen.
Result
|
Result |
Proceed to |
| All ECUs and sensors connected to the CAN communication system are
not displayed on the
screen.
(Open in CAN bus main wire or short in CAN bus wire or DLC3 branch wire malfunction) |
A |
| One of the ECUs and sensors connected to the CAN communication
system is not displayed on the
screen.
(Open in ECU or sensor branch wires, or communication interrupted) |
B |
| Some of the ECUs and sensors connected to the CAN communication
system are not displayed on
the screen. During this check, some ECUs and sensors repeatedly appear
and disappear from the
screen.
(Open in one side of ECU or sensor branch wires) |
C |
| All ECUs and sensors connected to the CAN communication system are
displayed on the screen.
(CAN bus circuit is currently normal) |
D |
NOTICE: Non-installed ECUs or sensors will not be displayed.
Do not mistake them for being in the communication stop mode.
HINT: The ECUs and sensors that repeatedly appear and disappear from the screen during this check are considered normal. (The response to the intelligent tester and the tester display are affected by signals output from other ECUs which have an open circuit in either of their CAN branch wires.)
4 CHECK CAN BUS WIRE
- Check the CAN bus wires (See page CA-35).
HINT: If the area where an open or short is occurring in a CAN bus wire can be determined, refer to the "PROBLEM SYMPTOMS TABLE"
5 DTC COMBINATION TABLE
- Confirm trouble according to the combination of output DTCs regarding the CAN communication system
6 CIRCUIT INSPECTION
7 IDENTIFICATION OF PROBLEM
8 REPAIR OR REPLACE
9 CONFIRMATION TEST
END
System description
1. BRIEF DESCRIPTION
The CAN (Controller Area Network) is a serial data
communication system for real time application. It is
a vehicle multiplex communication system which
has a high commun ...
Problem symptoms table
RESULT LIST OF CHECK CAN BUS LINE
Symptom
Suspected Area
All ECUs and sensors connected to the CAN
communication system are not displayed on intelligent
tester
CAN ...
Other materials:
Removal
1. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
2. REMOVE V-BANK COVER SUB-ASSEMBLY (See
page EM-28)
3. REMOVE PURGE VSV
(a) Disconnect the purge VSV connector.
(b) Disconnect the 2 purge line hoses from the purge
VSV.
(c) Remove the purge VSV from the air cleaner hose.
(d) R ...
TRAC OFF Indicator Light Remains ON
DESCRIPTION
The skid control ECU is connected to the combination meter via CAN and
multiplex communications.
When the traction OFF switch is turned on, the TRAC OFF indicator light will
come on (for 2WD model).
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
When replacing the brake actu ...
Basic inspection
(a) WHEN MEASURING RESISTANCE OF
ELECTRONIC PARTS
(1) Unless otherwise stated, all resistance
measurements should be made at an ambient
temperature of 20°C (68°F). Resistance
measurements may be inaccurate if measured
at high temperatures, i.e. immediately after the
vehicle has been running ...
