Toyota Sienna Service Manual: Steering Angle Sensor Circuit Malfunction
DTC C1231/31 Steering Angle Sensor Circuit Malfunction
DESCRIPTION
The steering angle sensor signal is sent to the skid control ECU through the CAN communication system.
When there is a malfunction in the communication, it will be detected by the
diagnosis function.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
- When U0073/94, U0100/65, U0123/62, U0124/95 or U0126/63 are output accompanied with C1231/ 31, inspect and repair the trouble areas indicated by U0073/94, U0100/65, U0123/62, U0124/95 or U0126/63 first.
- When the speed sensor or the yaw rate sensor has trouble. DTCs for the steering angle sensor may be output even when the steering angle sensor is normal. When DTCs for the speed sensor or yaw rate sensor are output accompanied with other DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate sensor first, and the n inspect and repair the steering angle sensor.
1 INSPECT STEERING ANGLE SENSOR
(a) Remove the steering wheel and the column lower cover.
(b) Disconnect the steering angle sensor connector.
(c) Turn the ignition switch to the ON position.
(d) Measure the voltage according to the value(s) in the table below.
Standard voltage 
(e) Measure the voltage according to the value(s) in the table below.
Standard voltage 
REPLACE STEERING ANGLE SENSOR
SM Solenoid Circuit
DTC C1225/25 SM Solenoid Circuit
DESCRIPTION
This solenoid turns on when receiving signals the ECU and controls the
pressure acting on the wheel
cylinders to control the braking force.
WIRIN ...
Stuck in Deceleration Sensor
DESCRIPTION
The yaw rate sensor and deceleration sensor signal is sent to the skid
control ECU through the CAN
communication system. When there is a malfunction in the communication, it will
...
Other materials:
Adjustment
1. VEHICLE PREPARATION FOR FOG LIGHT AIMING
Prepare the vehicle:
Ensure there is no damage or deformation to the
body around the fog lights.
Fill the fuel tank.
Make sure that the oil is filled to the specified
level.
Make sure that the coolant is fi ...
Inspection
1. INSPECT THERMOSTAT
(a) Inspect the thermostat.
HINT:
The valve opening temperature is inscribed on the
thermostat.
(b) Immerse the thermostat in water and gradually heat
the water.
(c) Check the valve opening temperature.
Valve opening temperature:
80 to 84°C (176 to 183°F) ...
Inspection
1. INSPECT FUEL PUMP
(a) Inspect fuel pump resistance.
(1) Using an ohmmeter, measure the resistance
between the terminals.
Standard resistance
(b) Inspect fuel pump operation
(1) Apply battery voltage to both the terminals.
Check that the pump operates.
NOTICE:
These te ...
