SL 600 (129.076) V12-6.0L (120.981) (1995)
Refrigerant Pressure Sensor / Switch: Testing and Inspection
Pressure Switch S32
TESTING PROCEDURE:
Condenser Fan Motor Switch (Pressure Switch) [S32]
1. Switch on ignition.
2. Bridge terminals on pressure switch [S32]. If the auxiliary fan does not run at speed 2, the fault is not in the pressure switch (see electrical circuit
diagrams).
3. Connect high-pressure gauge to connection (arrow).
4. Switch on air conditioning system.
5. Set blower switch to speed 4:
-
Allow engine to idle (coolant temperature < 100 °C), until pressure indicated on high-pressure gauge reaches approx 22/18±0.5 bar
(corresponding to pressure of approx. 20/16±0.5 bar on pressure switch [S32]), increase engine speed slowly, if required. If auxiliary fan does
not switch to speed 2, the pressure switch is defective.
-
Allow engine to idle (coolant temperature < 100 °C), until pressure indicated on high-pressure gauge reaches approx. 17/14±0.5 bar
(corresponding to pressure of approx. 15/12±0.5 bar on pressure switch [S32]), disconnect plug on pressure switch (S31/1), if required. If
auxiliary fan speed 2 does not switch off, the pressure switch (S32) is defective, or check control for relay K9 using electrical circuit diagram.
TEST DATA:
Pressure switch (S32) for fluid reservoir for auxiliary fan speed 2:
Switch-off pressure: 15±0.5 bar
Switch-on pressure: 20±0.5 bar