I was replacing the P/S pump on my 1989 GTU. When I took off the old P/S pump, the wire connected to the pressure switch service came off. I took the wire off and I’m running the car without it. Can any problems occur without the pressure switch service or is it necessary to have it?

 

Good question..... I want to say no. When I did the 1j swap in my fd, I retained ps and did not install a pressure switch. I've noticed no problems or anything. Driving feels fine and everything.

maybe the ps system is outlined in the fsm. If it is, it will explain the exact function of the pressure switch. With that information, you'll be able to determine what would happen without it.

nothing..... the answer is nothing.

 

Same thing happened to me about a year ago. Fortunately, I had a spare pressure switch. You can't buy pressure switches anymore from either Mazda or aftermarket. I think that broken wire may be repairable. But to your question. I don't have an answer. Sorry. Cheers and happy holiday .

 

Power steering pressure switch is just signal for ECU to compensate on idle for higher load.