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.
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.
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
4 CHECK WIRE HARNESS (CG OF DLC3 - BODY GROUND)
- Measure the resistance according to the value(s) in the table below.
Standard resistance
5 CHECK WIRE HARNESS (TC OF DLC3 - BODY GROUND)
- Measure the resistance according to the value(s) in the table below.
Standard resistance
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
2 CHECK CONNECTORS
Turn the ignition switch to the LOCK ...
Other materials:
Speed warning
Concept
A speed limit can be set that when reached will
cause a warning to be issued.
General information
The warning is repeated if the vehicle speed exceeds
the set speed limit again, after it has dropped
below it by 3 mph/5 km/h.
Adjusting
Via iDrive:
1. "CAR".
2. "Settings".
3. "General settin ...
Mass or Volume Air Flow Circuit
DESCRIPTION
The Mass Air Flow (MAF) meter is a sensor that measures the amount of air
flowing through the throttle
valve. The ECM uses this information to determine the fuel injection time and to
provide appropriate airfuel
ratio. Inside the MAF meter, there is a heated platinum wire whic ...
Problem symptoms table
HINT:
Proceed to the troubleshooting for each circuit in the table
below.
AIRBAG SYSTEM
Symptom
Suspected Area
The SRS warning light goes off after the primary
check, but then comes on.
SRS Warning Light Remains ON
When the ignition switch is turned to t ...
