Chrysler Repair: Neon: power steering pressure sensor outside set range (code 0551), continuity tester, side fender

Question
hi, as it states in the subject matter i need help finding out why the power steering pressure sensor out side set range means the engine light comes on sporadicly i would appreciate if you could shed some light on the subject as the car service firm couldn't tell me what that meant on a diagnostic check.
many thanks.

Answer
Hi Fiona,
The pressure sense switch has the purpose of increasing the idle speed when you are trying to park the car and having to turn the steering wheel when you are moving very slowly or not at all. It is a simple device that screws into power steering gear and has a wire that is connected to the engine computer. When the pressure demand increases the switch opens and that sends a voltage signal to increase the idle, when the pressure drops to normal the switch closes and the idle speed goes back to normal. The check engine light means the engine computer didn't detect any signal from the switch when it should have seen it.  
It could either be the switch is not responding as it should or the wires (white or black/tan in color) from the switch to the engine computer or chassis ground is disconnected. It is under the car so may have simply been mechanically disconnected by having gotten caught on something (just plug it back into the switch).
It would be simple for some one with minimal skills to jack up one side of the vehicle, go to the power steering gear, locate the switch on the rear side, find the two electrical wires on it or nearby to see if they are connected and in good condition. He could even verify the white wire connection is patent from the switch to pin 45 of the engine computer, and also that a second wire (black/tan in color) at the switch is connected to the chassis ground point nearby on the top surface of the driver side fender (open the hood), and also close to the engine controller plug that carries wires # 41-80. He would use a continuity tester or ohmmeter to verify the connections. If the wires are connected properly to the switch and in turn they are connected to the points I described, then I would believe the switch itself if not working properly and should be replaced, which is a simple unscrew/screw-in procedure using a 7/8" deep well socket and being careful not to overtighten it (6 foot-pounds torque, maximum). It should cost around $10 for the switch. The labor time should be 1/2 hour or so.
Roland
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