Toyota Sienna Service Manual: Diagnosis Circuit
DESCRIPTION
DTC output mode is set by connecting terminals TC and CG of the DLC3.
DTCs are displayed by blinking the SRS warning light.
HINT:
- When each warning light stays blinking, a ground short in the wiring of terminal TC of the DLC3 or an internal ground short in each ECU is suspected.
- A DTC output mode signal is transmitted through BEAN and CAN to each ECU including the center airbag sensor assembly. Thus when all systems do not enter DTC output mode, there may be an ECM malfunction
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK MULTIPLEX COMMUNICATION SYSTEM
- Check if the multiplex communication system DTC is output.
HINT: The center airbag sensor assembly of this system is connected to the multiplex communication system.
Therefore, before starting troubleshooting, make sure to check that there is no trouble in the multiplex communication system.
OK: The Multiplex communication system DTC is not output.
REPAIR CIRCUITS INDICATED BY
OUTPUT
DTCS
2 CHECK CAN COMMUNICATION SYSTEM
- Use the intelligent tester to check if the CAN communication system is functioning normally.
HINT: The ECM is connected to the CAN communication system. Therefore, before starting troubleshooting, make sure to check that there is no trouble in the CAN communication system.
OK: The CAN communication system is functioning normally.
REPAIR CAN COMMUNICATION
CIRCUIT
3 CHECK WIRE HARNESS (TC OF DLC3 - TC OF ECM)
- Turn the ignition switch to the LOCK position.
- Disconnect the connector from the ECM.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
REPAIR OR REPLACE WIRE
HARNESS (TC
OF DLC3 - TC OF ECM)
4 CHECK WIRE HARNESS (CG OF DLC3 - BODY GROUND)
- Measure the resistance according to the value(s) in the table below.
Standard resistance
REPAIR OR REPLACE WIRE
HARNESS (CG
OF DLC3 - BODY GROUND)
5 CHECK WIRE HARNESS (TC OF DLC3 - BODY GROUND)
- Measure the resistance according to the value(s) in the table below.
Standard resistance
REPAIR OR REPLACE WIRE
HARNESS OR
EACH ECU
REPLACE CENTER AIRBAG SENSOR ASSEMBLY
SRS Warning Light does not Come ON
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK BATTERY
Measure the voltage of the battery.
Standard voltage:
11 to 14 V
CHECK AND REPLACE BATTERY OR
CHARGING SYSTEM
2 CHECK CO ...
Other materials:
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 no ...
ABS Warning Light Remains ON
DESCRIPTION
If any of the following is detected, the ABS warning light remains on.
The skid control ECU connectors are disconnected from the skid control
ECU.
There is a malfunction in the skid control ECU internal circuit.
There is an open in the harness between the combination meter an ...
On-vehicle inspection
1. INSPECT FRONT AXLE HUB BEARING BACKLASH
(a) Using a dial gauge, check for backlash near the
center of the axle hub.
Maximum:
0.05 mm (0.0020 in.)
If backlash exceeds the maximum, replace the
bearing.
NOTICE:
Ensure that the dial gauge is set at right angles
to the measurement surface ...
