Programming and Relearning
POWER STEERING: POWER STEERING SYSTEM: CALIBRATION
1. ROTATION ANGLE SENSOR INITIALIZATION AND TORQUE SENSOR ZERO POINT CALIBRATION (When not using the Techstream)
NOTICE:
Clear the rotation angle sensor calibration value, initialize the rotation angle sensor, and calibrate the torque sensor zero point if any of the following has occurred:
* The power steering ECU has been replaced.
* The power steering column has been replaced.
* Steering effort differs between left and right.
HINT
Conducting torque sensor zero point calibration will cause the power steering ECU to enter test mode. When entering test mode, the power steering ECU will automatically perform assist map writing.
(a) Check for DTCs.
(1) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
NOTICE:
* If DTC C1516 (Torque Sensor Zero Point Adjustment Incomplete) is stored, the torque sensor zero point cannot be calibrated. Clear the DTC before starting calibration.
* If DTC C1526 (Rotation Angle Sensor Initialization Incomplete) is stored, the rotation angle sensor cannot be initialized. Clear the DTC before starting initialization.
* If DTCs other than C1516 and C1526 are output, refer to the "Diagnosis Trouble Code Chart" Power Steering System.
(b) Pre-calibration check.
(1) Turn the ignition switch off.
(2) Disconnect the C34 power steering ECU connector.
(3) Turn the ignition switch to ON.
(4) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
NOTICE:
If the measured value is 9 V or less, the calibration cannot be performed. Recharge or replace the battery and then perform the calibration.
(5) Turn the ignition switch off.
(6) Connect the C34 power steering ECU connector.
(c) Erase sensor calibration value.
(1) Set the steering wheel to the center point and align the front tires straight ahead.
(2) Turn the ignition switch off.
(3) Using SST, connect terminals 12 (TS) and 4 (CG) of the DLC3.
Text in Illustration
SST : 09843-18040
NOTICE:
Connect the terminals to the correct positions to avoid a malfunction.
(4) Turn the ignition switch to ON and then connect and disconnect terminals 13 (TC) and 4 (CG) at least 20 times in 20 seconds.
(5) Check that the EPS warning light blinks and then remains illuminated.
Text in Illustration
HINT
The EPS warning light illumination indicates that DTCs C1515 and C1525 have been stored.
(6) Turn the ignition switch off.
NOTICE:
After erasing the sensor calibration value, the rotation angle sensor initialization or zero point calibration cannot be performed if the ignition switch is ON.
(d) Torque sensor zero point calibration.
NOTICE:
As the torque sensor zero point calibration cannot be performed if DTC C1515 has not been stored, be sure to perform the sensor calibration value erasure before performing the torque sensor zero point calibration.
(1) Set the steering wheel to the center point and align the front tires straight ahead.
(2) Turn the ignition switch off.
(3) Using SST, connect terminals 12 (TS) and 4 (CG) of the DLC3.
Text in Illustration
SST : 09843-18040
(4) Turn the ignition switch to ON and then connect terminals 13 (TC) and 4 (CG).
NOTICE:
Do not touch the steering wheel during the calibration (for 3 seconds).
HINT
The EPS warning light remains illuminated even when the calibration has been completed.
(5) With terminals 12 (TS) and 4 (CG), and 13 (TC) and 4 (CG) connected, and the ignition switch ON, continue to perform the rotation angle sensor initialization.
(e) Rotation angle sensor initialization.
NOTICE:
As the rotation angle sensor initialization cannot be performed if DTC C1525 has not been stored, be sure to perform the sensor calibration value erasure and torque sensor zero point calibration before performing the rotation angle sensor initialization.
(1) Set the steering wheel to the center point and align the front tires straight ahead.
NOTICE:
Make sure that terminals 12 (TS) and 4 (CG), and 13 (TC) and 4 (CG) are connected, and the ignition switch is ON.
(2) Disconnect and reconnect terminals 13 (TC) and 4 (CG).
HINT
Disconnecting and reconnecting terminals 13 (TC) and 4 (CG) allows the power steering ECU to change modes to rotation angle sensor initialization mode.
(3) Turn the steering wheel to the left and right 45° or more. Then turn the steering wheel to the left or right 90° or more.
NOTICE:
Do not turn the steering wheel sharply.
HINT
* When the calibration has been completed normally, the EPS warning light goes from being illuminated to blinking (at 0.125 second intervals).
* The EPS warning light remains illuminated if the calibration has not been completed normally. In this case, check for DTCs and perform calibration again if DTC C1515 and/or C1525 is/are output. When performing the calibration again, perform it in the following order: sensor calibration value erasure, torque sensor zero point calibration, and rotation angle sensor initialization. If DTCs other than C1515 and C1525 are output, go to "Diagnostic Trouble Code Chart" Power Steering System.
* If the assist map is not recorded, DTC C1581 (Assist Map Un-Writing) is stored, and the EPS warning light illuminates. Also, after the assist map is recorded, if data that does not match the vehicle specifications is received through CAN communication, DTC C1582 (Assist Map Number Mismatch) is stored.
(4) Disconnect SST from the DLC3.
(5) Turn the ignition switch off.
2. ROTATION ANGLE SENSOR INITIALIZATION AND TORQUE SENSOR ZERO POINT CALIBRATION (When using the Techstream)
NOTICE:
Clear the rotation angle sensor calibration value, initialize the rotation angle sensor, and calibrate the torque sensor zero point if any of the following has occurred:
* The power steering ECU has been replaced.
* The power steering column has been replaced.
* Steering effort differs between left and right.
HINT
Conducting torque sensor zero point calibration will cause the power steering ECU to enter test mode. When entering test mode, the power steering ECU will automatically perform assist map writing.
(a) Inspection before calibration.
(1) Turn the ignition switch off.
(2) Connect the Techstream to the DLC3.
(3) Turn the ignition switch to ON.
(4) Turn the Techstream on.
(5) Enter the following menus: Chassis / EMPS / Data List / IG Power Supply.
(6) Check the values by referring to the table below.
EMPS
Standard voltage:
11 to 14 V
NOTICE:
If the IG power supply voltage is 9 V or less, calibration cannot be performed. In this case, charge or replace the battery, and then perform calibration.
(b) Rotation angle sensor calibration value clear, rotation angle sensor initialization, and torque sensor zero point calibration.
NOTICE:
* If DTC C1516 (Torque Sensor Zero Point Adjustment Incomplete) is stored, the torque sensor zero point cannot be calibrated. Clear the DTC before starting calibration.
* If DTC C1526 (Rotation Angle Sensor Initialization Incomplete) is stored, the rotation angle sensor cannot be initialized. Clear the DTC before starting initialization.
(1) Turn the ignition switch off.
(2) Connect the Techstream to the DLC3.
(3) Turn the ignition switch to ON.
(4) Turn the Techstream on.
(5) Enter the following menus: Chassis / EMPS / Utility / Torque Sensor Adjustment.
(6) Following the procedures on the Techstream display to clear the rotation angle sensor calibration value, initialize the rotation angle sensor value, and calibrate the torque sensor zero point.
NOTICE:
* Set the steering wheel to the center point and align the front tires straight ahead.
* Do not turn the steering wheel sharply.
* Do not touch the steering wheel during the torque sensor zero point calibration (for 3 seconds).
HINT
* When the calibration has been completed normally, the EPS warning light goes from being illuminated to blinking (at 0.125 second intervals).
* The EPS warning light remains illuminated if the calibration has not been completed normally. In this case, check for DTCs and perform calibration again if DTC C1515 and/or C1525 is/are output. When performing the calibration again, perform it in the following order: sensor calibration value erasure, torque sensor zero point calibration, and rotation angle sensor initialization. If DTCs other than C1515 and C1525 are output, go to "Diagnostic Trouble Code Chart" Power Steering System.
* If the assist map is not recorded, DTC C1581 (Assist Map Un-Writing) is stored, and the EPS warning light illuminates. Also, after the assist map is recorded, if data that does not match the vehicle specifications is received through CAN communication, DTC C1582 (Assist Map Number Mismatch) is stored.