Operation CHARM: Car repair manuals for everyone.

Menu 3 = Input Signals

Menu 3 = Input signals

Pressure switch

Important notes
- A defective pressure-operated switch adopts a condition which Is defined by the HF sensor as being a standard operational condition. Example: if the pressure-operated switch diaphragm is deformed, the switch assumes the closed state, therefore OK state, even if the tire pressure is too low.
- The HF sensor must be tested and OK before the pressure-operated switch can be diagnosed correctly.


Pressure switch

Note: 2 pressure-operated switches (offset by 180°) must be checked per wheel

Align pressure-operated switch with HF sensor. Then
a) Tire pressure greater than switching pressure

Required display: CLOSED

If the "OPEN" display appears,

- the distance or offset between switch and HF sensor is too great or

- the pressure-operated switch is defective

b) Tire pressure less than switching pressure

Required display: OPEN

If the "CLOSED" display appears, the pressure-operated switch is defective.