Power Steering System: Calibration

TORQUE SENSOR ZERO POINT CALIBRATION (USING TECHSTREAM)
NOTE: Perform the torque sensor zero point calibration when any of the following conditions occur.
- The steering column assembly (containing the torque sensor) has been replaced.
- The power steering ECU has been replaced.
- The steering wheel has been replaced.
- The steering gear assembly has been replaced.
- There is a difference in steering effort between turning right and left.
1. Center the steering wheel and align the front wheels straight ahead.
2. Connect a Techstream to the DLC3.
3. Turn the ignition switch to ON and turn the tester on.
4. Enter the following menus:
  Chassis / EMPS / Utility / Torque Sensor Adjustment.
5. Initialize the torque sensor zero point calibration signal and perform the zero point calibration by following the prompts on the tester screen.
  NOTE: Do not touch the steering wheel during the calibration.
6. Confirm that no DTCs are output after the zero point calibration is completed.
  1. When DTC C1515/15 is output, see DTC C1515/15 TORQUE SENSOR ZERO POINT ADJUSTMENT IS NOT INITIALIZED .
  2. When DTC C1516/16 is output, see DTC C1516/16 TORQUE SENSOR ZERO POINT ADJUSTMENT INCOMPLETE .
  3. When DTC C1534/34 is output, see DTC C1531/31 EPS ECU CIRCUIT MALFUNCTION; DTC C1532/32 EPS ECU CIRCUIT MALFUNCTION; DTC C1533/33 EPS ECU CIRCUIT MALFUNCTION; DTC C1534/34 EPS ECU CIRCUIT MALFUNCTION; DTC C1535/35 STEERING WHEEL LOCATION DATA ERROR .
TORQUE SENSOR ZERO POINT CALIBRATION (USING SST CHECK WIRE)
1. Center the steering wheel and align the front wheels straight ahead.
2. Initialize the torque sensor zero point calibration signal.
  HINT:
  
  If the power steering ECU is replaced, initialization is not necessary.
  
  Fig 1: Identifying Front View Of DLC3 Connector Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Stop the vehicle and turn the ignition switch to OFF.
  2. Turn the ignition switch to ON and wait for 3 seconds or more.
  3. Using SST, connect terminals TS and CG of the DLC3.
    SST 09843-18040
  4. Using SST, connect terminals TC and CG of the DLC3.
    SST 09843-18040
  5. Disconnect and reconnect terminal TC of the DLC3 20 times or more within 20 seconds.
  6. Check that PS warning light comes on and DTC C1515/15 is output.
  7. Turn the ignition switch to OFF.
    HINT:
    
    Perform the torque sensor zero point calibration after turning the ignition switch to OFF.
3. Perform the torque sensor zero point calibration.
  NOTE: Do not touch the steering wheel during the calibration.
  
  HINT:
  
  Check whether any DTCs except C1515/15 are output.
  1. Stop the vehicle and turn the ignition switch to OFF.
  2. Using SST, connect terminals TS and CG of the DLC3 and turn the ignition switch to ON.
    SST 09843-18040
  3. Wait for 5 seconds after the PS warning light comes on.
  4. Confirm that the PS warning light blinks at intervals of 0.125 seconds (4Hz blink).
  5. Disconnect the SST.
    SST 09843-18040
  6. Confirm that no DTCs are output.
    1. When DTC C1515/15 is output, see DTC C1515/15 TORQUE SENSOR ZERO POINT ADJUSTMENT IS NOT INITIALIZED .
    2. When DTC C1516/16 is output, see DTC C1516/16 TORQUE SENSOR ZERO POINT ADJUSTMENT INCOMPLETE .
    3. When DTC C1534/34 is output, see DTC C1531/31 EPS ECU CIRCUIT MALFUNCTION; DTC C1532/32 EPS ECU CIRCUIT MALFUNCTION; DTC C1533/33 EPS ECU CIRCUIT MALFUNCTION; DTC C1534/34 EPS ECU CIRCUIT MALFUNCTION; DTC C1535/35 STEERING WHEEL LOCATION DATA ERROR .
      
      Fig 2: PS Warning Light 4Hz Blinking Pattern
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002