2892400 - 5040BA Check operation of three-stage pressure switch
Wiring diagrams and pins
Check 1st stage (approx. 2.5 bar):
- Disconnect the pressure switch from its pipe (see PROCEDURES OP.) and check that the circuit between pins 3 and 4 is open.
- Reconnect the pressure switch to its pipe: the contact between pins 3 and 4 closes.
- Reconnect the electrical connection of the pressure switch and switch on the system by pressing the A/C button on the air conditioner control panel.
- Wait a few minutes. At the same time make sure that the compressor switches on normally.
The calibration of the 1st stage is:
- contact opens 2.2 - 2.7 bar
- contact closes 2.3 - 2.9 bar
Check 2nd stage (approx. 15 bar):
- Operate the system with the car stopped.
- Wait a few minutes: the contact between pins 1 and 2 closes. At the same time make sure that the fan comes on.
The calibration of the 2nd level is:
- contact closes 14.2 - 16.2 bar;
- contact opens 10.3 - 12.3 bar.
Check 3rd stage (approx. 28 bar):
- It is advisable not to allow the pressure of the circuit to increase to that value, which is too close to the safety limits.
![]() | The calibration of this level cannot therefore be checked on the car. |
The calibration of the 3rd level is:
- contact opens 25 - 30 bar;
- contact closes 19 - 24 bar.