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I had a similar experience as Bill except it was the oil pressure sensor. Nothing gets you on the ground faster than a zero oil pressure alarm. Happened twice. The first time I replaced the sensor and the second time was about a month later. I figured it must have been a connection of the DPU so I replaced the cable, connections and even removed the DPU to verify proper function. I swapped fuel pressure and oil pressure inputs to be sure it wasn't a flaky A-D channel on the DPU. After weeks of mucking about it turns out that the new sensor was flaky. A call to JP got the "You installed it you bought it" response. My reply? Foxtrot Yankee.
I never much cared for the Media Mate sensors because they used crummy "Faston" spade connections that treat millivolt signals like a junk yard dog so I decided to make something better.
Understand that these types of pressure sensors use strain gages (resistors that vary with strain) in a Whetstone bridge configuration. The output is proportional to the input and the pressure applied, or millivolts per volt of excitation per PSI of applied pressure. If at 50 PSI and 5 volt excitation you get a 5 millivolt output then at 10 volt excitation you would get 10 millivolts at the same applied pressure. VM1000 uses 5 volt excitation.
For the oil pressure I ended up selecting the Honeywell 19C series in 0-100 PSI range (19C100PG4K) http://sensing.honeywell.com/index.cfm?ci_id=140301&la_id=1&pr_id=145986
and machining a backshell out of aluminum to accept a MIL Spec 4 pin connector. (see attached picture of the modeled assembly). You need access to a lathe and a mill for about an hour to make the backshell. The sensor was about $110 and the connector another $20.
The fuel pressure sensor needs to have a 0-50 PSI range so the part number would be 19C50PG4K.
The sensor has been installed for over 2 years without any problem.
Any brave soul that wants to follow my footsteps to make their own backshell, email me and I'll send you a drawing, or better yet, the SolidWorks model.
Regards
Brent Regan
pressure sensor.jpg
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