Toyota Sienna Service Manual: Open in ABS Solenoid Relay Circuit
DESCRIPTION
This relay supplies power to each ABS solenoid.
Immediately after the ignition switch is turned to the ON position, the relay turns on if the solenoid is determined to be normal as a result of self-diagnosis during initial check.
The relay turns off if an open/short is detected.
If the voltage supplied to the motor relay (+BS) is below the DTC detection threshold due to low voltage from the battery/alternator, the DTCs may be stored.
WIRING DIAGRAM
Refer to DTCs C0226/21, C0236/22, C0246/23 and C0256/24 (See page BC-29).
INSPECTION PROCEDURE
1 INSPECT FUSE (ABS 2 FUSE)
(a) Remove the ABS 2 fuse from the FL block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
2 INSPECT SKID CONTROL ECU (+BS TERMINAL VOLTAGE)
(a) Install the ABS 2 fuse.
(b) Disconnect the skid control ECU connector.
(c) Measure the voltage according to the value(s) in the table below
Standard voltage
3 INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance 
4 RECONFIRM DTC
(a) Clear the DTCs (See page BC-10).
(b) Start the engine.
(c) Drive the vehicle at the speed of 6 km/h (4 mph) or more.
(d) Check that the same DTCs are recorded (See page BC- 10).
HINT:
- Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.
- If a speed signal of 6 km/h (4 mph) or more is input to the skid control ECU, with the ignition switch on and the stop light switch off, the ECU performs selfdiagnosis of the motor and solenoid circuits.
Result
HINT:
- If any DTCs are output while jiggling a connector or wire harness of the brake actuator (skid control ECU), inspect and repair the connector or wire harness.
- If the normal system code is output, slightly jiggle the connectors, wire harnesses, and fuses of the brake actuator assembly. Make sure that no DTCs are output.
- These DTCs may be memorized due to a malfunction in the connector terminal connection, etc.
REPLACE BRAKE ACTUATOR ASSEMBLY
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 t ...
Low Battery Positive Voltage
DTC C1241/41 Low Battery Positive Voltage
DESCRIPTION
If there is a problem with the brake actuator assembly (skid control ECU)
power supply circuit, the skid
control ECU outputs the DTC and proh ...
Other materials:
Terminals of ECU
1. COMBINATION METER ASSEMBLY
*1: with Power Rear No. 2 Seat with Stowing Function
*2: with Theft Deterrent System
Waveform 1 (Reference) : Using an oscilloscope:
OK:
HINT:
As vehicle speed increases, the cycle of the signal
waveform narrows.
Wavefor ...
Brake
GENERAL MAINTENANCE
1. INSPECT BRAKE LINE PIPES AND HOSES
HINT:
Check the entire circumference and length of the brake
hoses using a mirror as required in a well-lighted area.
Turn the front wheels fully right or left before checking
the front brakes.
(a) Check all the brake lines and h ...
On-vehicle inspection
1. INSPECT BRAKE BOOSTER
(a) Air tightness check.
(1) Start the engine and stop it after 1 or 2 minutes.
Depress the brake pedal several times slowly.
HINT:
If the pedal goes down farthest at the 1st time,
and gradually rises at the 2nd or 3rd time, the
booster is airtight.
(2) Depre ...
