Toyota Sienna Service Manual: 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 actuator assembly, perform zero point calibration (See page BC-70).
1 CHECK CAN COMMUNICATION SYSTEM
(a) Check if the CAN communication system DTC is output (See page CA-17).
Result 
2 CHECK MULTIPLEX COMMUNICATION SYSTEM
(a) Check if the multiplex communication system DTC is output (See page MP-14).
Result 
3 CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED
(a) Check if the skid control ECU connector is securely connected.
OK: The connector is securely connected.
4 CHECK BATTERY
(a) Check the battery voltage.
Standard voltage: 11 to 14 V
5 INSPECT SKID CONTROL ECU (CSW TERMINAL)
(a) Disconnect the skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
6 INSPECT COMBINATION METER ASSEMBLY
(a) Reconnect the skid control ECU connector.
(b) Perform Active Test of the combination meter (meter CPU) using the intelligent tester (See page ME-19).
OK: The TRAC OFF indicator light turns on or off in accordance with the intelligent tester.
HINT: If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (See page BC-79).
REPLACE BRAKE ACTUATOR ASSEMBLY
7 INSPECT TRACTION OFF SWITCH
(a) Disconnect the traction OFF switch connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
8 CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - TRACTION OFF SWITCH)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance 
HINT: If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (See page BC-79).
REPLACE BRAKE ACTUATOR ASSEMBLY
Brake Warning Light Remains ON
DESCRIPTION
The BRAKE warning light comes on when the brake fluid is insufficient, the
parking brake is applied or the
EBD is defective.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
When rele ...
TRAC OFF Indicator Light does not Come 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 o ...
Other materials:
Data list / active test
1. READ DATA LIST
HINT:
Using the intelligent tester's DATA LIST allows switch,
actuator and other item values to be read without
removing any parts. Reading the DATA LIST early in
troubleshooting is one way to save time.
Connect the intelligent tester with CAN VIM to the
DLC3.
&n ...
System description
1. DESCRIPTION OF OCCUPANT CLASSIFICATION SYSTEM
GENERAL DESCRIPTION.
In the occupant classification system, the
occupant classification ECU calculates the
weight of the occupant based on a signal from
the occupant classification sensors. This system
recognizes the occu ...
Communication Error from ECM to Distance
Control ECU
DTC P1616 Communication Error from ECM to Distance
Control ECU
DTC U0100 Lost Communication with ECM/PCM "A"
DESCRIPTION
The ECM receives signals from each sensor and ECU, then sends signals such as
A/T signals, cruise
control operation signals, low speed operation signals, brake co ...
