analog Input 2

[SPOOLIN]

I was trying to setup a map sensor on Analog Input 2 for a pressure sensor. Most of the pressure sensors have negative values for pressure at 0 volts. I can't seem to enter a negative value in the analog input 2 table(B6 input)

I was trying to use the built in inputs before resulting to using the analog 8 pin plug.

[Spunkster]

What sensor, and what values where youtrying to enter? What units are you using?

[SPOOLIN]

30-2130-75 AEM 5 BAR

I was using their voltage chart for -14.5 all the way to 60 psi.

http://aemelectronics.com/files/instruc ... Sensor.pdf

I havn't gotten it wired in yet but i was trying to do some pre-work. waiting on plug to get here tomorrow or the next.

[Spunkster]

A pressure sensor is not the same as a MAP sensor. A pressure sensor can only detect pressure, but a map sensor can detect vacuum as well as pressure.

For something like this I would recommend the PLX Devices SM - Vac/Boost.

[SPOOLIN]

Ok well I need to wire this Map sensor in. Will analog 2 work or do I need to use the aux 5v sensor inputs on the pig tail?

[Spunkster]

You will have to try using custom values and convert the voltage conversion table to Bar.

[SPOOLIN]

so i cant use settings->analog input 2 since i cant input negative values.
You are saying i need to use one of the 8 analog inputs and covert to BAR. I can do that, just making sure.

also, the sensor setup for an0 won't let me select anything other than volts for the unit.....

[Spunkster]

YOu must choose custom, pressure, and then you can select your units.

[SPOOLIN]

see attached

When i get this sensor running, are these settings going to display the pressure readings? Seems like its set to display voltage in the display and i can't choose anything else.

[Spunkster]

You will have to try it to see how it works.

[SPOOLIN]

so when i actually uploaded the file, it did try to show the reading, but i had issues. I had grounded the sensor ground on the sensor to the same ground path as VSS. Basically a primary ground. From tinkering and reading, Does the sensor ground need to go to the same type ground as other 5v sensors like TPS and MAP? Or required to go to the ground wires provided on the an0-7 sub harness? I'm in the process of redoing this sensors wiring since i was trying to use existing unused plugs on my aftermarket harness but the ground wires in those unused plugs all join together with other similar grounds not used by 5v sensors. I didnt notice this until i started metering.


Also, how many 5 volt sensors can the factory ECU support off its built in 5v pins?

[SPOOLIN]

......so does the signal ground of the aem sensor need to go to the ground pins on the analog input pigtail?

[Spunkster]

It needs to use the same ground that the 5v source uses. I do not know that limit of the number of sensors it can handle.

[SPOOLIN]

So if I use tps 5 volt supply, I gotta use the same ground that tps uses? What are the grounds on the pigtail for then?

[Spunkster]

Yes. That is for some sensors such as widebands that need a ground along with the signal wire from the wideband controller.