Power steering pressure switch

Hi all,
I have a fiesta finesse 1.3 of 1998 vintage, after having the power steering pump replaced I noticed that the engine speed wasn’t changing on full steering lock. I disconnected the connector from the top of the pressure switch and noticed that the engine speed increased and decreased when I put it back on.
surely this is the wrong way around? I intend checking the switch with an ohm meter to see if it is o.k.

any ideas?
thanks for looking.

Check that switch to make sure if the correct wire in on the correct pin - if the connector simply being on it decreases the RPM and rises when it is pulled off certainly indicates the condition. What I do not know is if when the steering pump no-load condition the switch is supposed to show - is correct.

So it may mean the switch is bad or they (rebuilders) put on the wrong switch - the vintage of the pump has me wondering if they rebuilt this; then used (installed) a different switch that is of the wrong type (NO when no load) or (NC when no load) NO = Normally Open, NC means Normally Closed

So since the idle rises when the connector is off, means it's looking for an OPEN condition in a high-torque turn - while the connector is on - creates a CLOSED condition, but idle drops. So the switch is reversed in the type it needs to be - Closed (should) means that there is a load on the steering (Turn effort) to change the systems ability to increase the torque at low-RPM or near low-idle and low-speed condition. So to me, unless there is some other pin configuration (Pins reversed - but only two?) If the switch has three pins and uses only two - you just have to use the DVM (meter tester) to find the common pin and just swap the other wire to the correct pin.

Might want to post a pic of what you're up against to help us, help you - to figure this out.