Toyota Sienna Service Manual: 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 and the skid control ECU.
HINT: In some cases, the intelligent tester cannot be used when the skid control ECU is abnormal.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED
(a) Check the skid control ECU connector's connecting condition.
OK: The connector should be securely connected.
2 INSPECT BATTERY
(a) Check the battery voltage.
Standard voltage: 11 to 14 V
2 INSPECT BATTERY
(a) Check the battery voltage.
Standard voltage: 11 to 14 V
3 INSPECT SKID CONTROL ECU (IG1 TERMINAL VOLTAGE)
(a) Disconnect the skid control ECU connector.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage 
4 INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)
(a) Turn the ignition switch off.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
5 CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND COMBINATION METER ASSEMBLY)
(a) Disconnect the combination meter connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance 
6 INSPECT COMBINATION METER ASSEMBLY
(a) Check the combination meter (See page ME-4).
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-7).
REPLACE BRAKE ACTUATOR ASSEMBLY
Open in Pump Motor Circuit
DTC C1251/51 Open in Pump Motor Circuit
DESCRIPTION
The motor relay (semiconductor relay) is housed in the brake actuator
assembly and drives the pump
motor based on a signal from the skid contro ...
ABS Warning Light does not Come ON
WIRING DIAGRAM
See page BC-47.
INSPECTION PROCEDURE
1 INSPECT ABS WARNING LIGHT
(a) Disconnect the skid control ECU connector.
(b) Turn the ignition switch to the ON position.
(c) Check that ...
Other materials:
Open in ABS Motor Relay Circuit
DESCRIPTION
The ABS motor relay supplies power to the ABS pump motor. While the ABS is
activated, the ECU turns
the motor relay on and operates the ABS pump motor.
If the voltage supplied to the motor relay (+BM) is below the DTCs detection
threshold due to low voltage
from the battery ...
Room Temperature Sensor Circuit
DESCRIPTION
This sensor detects the cabin temperature that is used as the basis for
temperature control and sends a
signal to the A/C amplifier.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 READ VALUE OF INTELLIGENT TESTER
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition s ...
Diagnostic trouble code chart
If a malfunction code is displayed during the DTC check,
check the circuit listed for that code in the table below.
(Proceed to the page given for that circuit.)
BACK DOOR CLOSER SYSTEM
DTC No.
Detection Item
Trouble Area
B2215
Back Door Closer Switch
...
