Component Location
Gerneral Description
A torque sensor, installed in the middle of steering column, is one unit composed of a main sensor and sub sensor. When the steering wheel is turned, the torsion bar is twisted in proportion to load of the wheel, and the assembled shaft turns as well. At this moment, due to twist of shaft, a change in the magnetic field is generated in main sensor coil surrounds the shaft and in the sub-sensor coil which is inside torque sensor. The change in current produced by this process is input to the EPS CM (MDPS=Motor Driving Power Steering). With a change of input sensor signal current, EPS CM determines driver's steering direction then, comparing current differences between the two sensors, the EPS CM determines whether main sensor is open/short. The Torque sensor can be damaged during disassembly of the sensor. You must disassemble or remove the sensor when removing or replacing the assembly.
DTC Description
This DTC refers to open/short of singnal circuit of Main torque sensor. This code is set if Main sensor output signal current is too high or low when torque sensor power is supplied normally. Due to this malfunction, DTC C1291 and C1292 can be set with this DTC at the same time.
DTC Detecting Condition
Item | Detecting Condition | Possible cause |
DTC Strategy | Voltage check
| Open/short in Main signal circuit Contact resistance in connections. Faulty sensor |
Enable conditions | Torque sensor voltage = 7.0 V
|
Threshold value | Main sensor output > 9.4 mA or < 0.6 mA
|
Diagnosis time | 1sec
|
Fail safe | Motor : OFF
Relay : OFF
Fail lamp : ON
Restoration condition : Power "OFF"
|
Diagnostic Circuit Diagram
Signal Waveform Data
Fig.1) when turning steering wheel to right
Fig.2) when turning steering wheel to left
Fig.1) When turning steering wheel to right : Check whether signal voltage rises to maximum 4V based on 2.5V and main sensor signal is the same as sub sensor signal. [Main sensor - Sub sensor] < 0.75 mA
Fig.2) When turning steering wheel to left : Check whether signal voltage descends to maximum 1V based on 2.5V and main sensor signal is the same as sub sensor signal. [Main sensor - Sub sensor] < 0.75 mA