Brake "safety" switch Question
If it has not been replaced, IE "getting old" it's probably all gummed up inside. All in the world that they are, is a piston that shuttles from one end to the other with a dip in the middle to allow the switch to shut off.
There used to be a tool, essentially a "dummy" switch which you could screw in to keep the piston centered. About all you can do is play with front/ rear pressure to center it.
Since it's likely gummed up, might be a good idea to replace it, or attempt to overhaul the one you have. If the O rings inside deteriorate, I would guess that the thing could interconnect the front / rear system, not a good thing.
It also seems likely that if one or both o rings leak past the piston, that the switch may not hold back the pressure and leak
The other possibility is to replace it with a pair of tees and do without.
If it has not been replaced, IE "getting old" it's probably all gummed up inside. All in the world that they are, is a piston that shuttles from one end to the other with a dip in the middle to allow the switch to shut off.
There used to be a tool, essentially a "dummy" switch which you could screw in to keep the piston centered. About all you can do is play with front/ rear pressure to center it.
Since it's likely gummed up, might be a good idea to replace it, or attempt to overhaul the one you have. If the O rings inside deteriorate, I would guess that the thing could interconnect the front / rear system, not a good thing.
It also seems likely that if one or both o rings leak past the piston, that the switch may not hold back the pressure and leak
The other possibility is to replace it with a pair of tees and do without.