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:
Removal
1. REMOVE NO. 1 ENGINE UNDER COVER (See page
EM-26)
2. REMOVE EXHAUST PIPE ASSEMBLY
for 2WD:(See page EX-2)
for 4WD:(See page EX-8)
3. DRAIN ENGINE COOLANT (See page CO-6)
4. DRAIN ENGINE OIL (See page LU-4)
5. REMOVE NO. 2 MANIFOLD STAY (See page EM-39)
6. REMOVE NO. 2 EXHAUST MANIFOLD HEAT ...
Road test
1. PROBLEM SYMPTOM CONFIRMATION
HINT:
The dynamic laser cruise control system has two cruise
control modes: the constant speed control mode and
vehicle-to-vehicle distance control mode.
The vehicle-to-vehicle distance control mode is
always selected when starting up the dynamic laser ...
Warning light and indicator light bulb check
(a) Check the warning lights.
(1) Release parking brake pedal.
(2) When the ignition switch is turned to the ON
position, check that the ABS warning light,
BRAKE warning light, VSC warning light, TRAC
OFF indicator light (2WD) and SLIP indicator
light stay on for approx. 3 seconds.
HI ...
