The short answer
Set the wheels straight and the steering wheel centred, connect the tool and go into the SAS or "steering angle" function. Depending on the car, it will ask you to turn the wheel from lock to lock and back to centre, or simply to confirm the straight-ahead position. When it is done, clear the ABS or ESP faults and check the warning light goes out.
The steering angle sensor tells the stability control (ESP) where you want to go. If, after some work on the car, the sensor thinks the wheel is turned when you are driving straight, the ESP stops trusting it and puts the warning light on. Or worse: it brakes a wheel when it shouldn't.
When it needs calibrating
- After a wheel alignment.
- When you replace the steering rack, column, steering wheel or the sensor itself.
- When you replace the ABS or ESP control unit.
- If the ESP warning light comes on after disconnecting the battery or after a knock to a wheel.
- If the tool shows a steering angle sensor code such as "not calibrated" or "out of range".
Alignment first. Calibrating the SAS does not straighten the steering wheel. If the wheel is off-centre when driving straight, the problem is the alignment and it has to be corrected at the garage first. Calibration only tells the sensor where the centre is.
Step by step
- Car on level ground, wheels straight and steering wheel centred.
- Connect the tool and identify the car. Ignition on; some models require the engine running.
- Go into Service → SAS (or into the ABS/ESP or steering control unit, depending on the make).
- Choose calibration. If there are two options, one usually clears the previous calibration and the other calibrates.
- Follow the on-screen prompts. Usually you turn the wheel to full left lock, full right lock and back to centre. On other cars you just confirm with the wheel straight.
- Switch the ignition off and on again if the tool tells you to.
- Read and clear the faults in the ABS, ESP and steering.
- Test the car in a straight line and through a couple of gentle bends. The warning light should stay off.
If the warning light won't go out
- Check the wheels really were straight when you calibrated. A few degrees out is enough to make it fail.
- Look at the angle value in live data: with the wheel straight it should be very close to 0°.
- Check for other ABS faults (wheel speed sensors, for example) that might be keeping the light on. We explain how in how to read and clear fault codes.
- On cars with electric power steering, a steering end-stop relearn may also be needed. If the tool offers it, do it after the SAS.
Which iCarsoft tools calibrate the SAS
It is one of the most widely available functions in the range. You will find it on the multi-brand tools (CR Pro, CR Pro+, CR Max P…), the V2.0 single-brand tools and most of the V1.0 tools too, whose service functions are oil reset and steering angle. If you are torn between a V1.0 and a V2.0, here are the differences: V1.0 vs V2.0.
