MAP Display Shows value of 57 "Hg All the Time

baldwin@dart.com

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I've just finished installing the Skyview EMS system and I've got everything nailed except for the MAP. When I view the value in the setup debug display it shows a typical value, but the EMS display always display about 57.6 (engine off and engine on, high idle). I've double checked all physical and electrical connections. The vacuum line is hooked up in parallel with dual PMags and an MGL Xtreme EFIS/EMS. The Xtreme shows correct values. The erroneous reading has been present from the start, when I first added the EMS box, and has always displayed 57.6. I've got the latest updates installed.

Ideas, anyone? I'm baffled.
 

Dynon

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What kind of engine? If you have a 912iS, there's a separate CAN MAP widget. If you don't have the iS but somehow have that widget up, you'd get invalid values too.
 

baldwin@dart.com

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Engine is a Mattituck IO-360, 180 HP. RV-8. The weird part is that in the setup-debug display the value is right (about 29") when the engine is off. It's only the display widget that doesn't show the value properly, neither on the graphic nor the digit. I looked hard for a units problem, but it looks like "Hg is used everywhere. Want me to upload pictures?
 

Dynon

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Yeah. Let's see the debug page, and also a picture with the sensor menu activated and the map widget highlighted on the layout editor. Also a picture of the EMS page with the wacky value.
 

baldwin@dart.com

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First pic is my XTreme EFIS showing "Hg. Engine is off.
Second pic is setup/debug screen.
Third pic is displayed "Hg. I configured the widget to show 0-60, so it shows the graphic location matches the digital value. But how can it be different from the value in the debug display? BTW, this same symptom was present before I upgraded to the latest Skyview version, so a software bug does not seem probable. Some weird configuration setting I've not been able to find?
Also, it's probably relevant that the widget graphic and digital value does not change when the engine is started (whereas the other displays do show a decreased "Hg when throttle is back in idle when running).
 

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Dynon

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Try removing the widget and adding it back perhaps. Is there more than one MAP listing on the sensor selection tool?
 

baldwin@dart.com

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Hey, I want you to know I really appreciate your support! I'm a software developer and am very familiar with problems like these ...

I checked the mapping menu and confirmed there's only one listing for MAP pressure, and the right hardware component is selected.

I removed the widget and put it back. No difference.

Then I used the Sensor Input Map display to disable the MAP input, exited setup, and the MAP widget displayed "CFG?" and the widget had an X on it. I rebooted, and the same display. I added the MAP back. I thought it odd the "Pressure" was the only option for "Function". Selected 100434-000 for hardware, then selected "MAP" to the right of that. No difference.

The fact remains that the debug display shows a good reading while the widget does not. Looks like a software bug to me, or a weird configuration setting that I can't locate.

Perplexing, isn't it?
 

baldwin@dart.com

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First of all, a big thanks to Jeff Fox and the rest of the support staff for helping me with this.

Problem was a bad crimp on the ground wire going into the sensor. Support was able to duplicate the debug readings when they unhooked the ground on their test jig. You guys rock!
 

Dynon

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I still don't get how it can read correctly on the debug page. As someone that's seen it all (I've been here a long while), this one is still baffling.
 
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