Hello

I've a question for the experts.

I have a Defi Boost sensor mounted in my car. The sensor itself has 3 cables (black,white and red).

I suppose that black is ground, red is current and white is the signal.

Can anyone confirm me that? Is the sensor connected to 12V, or just 5V?

I would like to wire the sensor to the ECU to be able to log boost.

Thanks

mlocatel

 

Sorry unable to reply to your question but if you haven't searched around much, people usually use the JDM Map 3bar sensor (now basically the stock evo X map sensor) to log boost.

Hope it helps if you're unlucky with the Defi.

 

+1 for jdm over gauge input.

 

sorry the JDM map sensor seems to be the popular choice on this forum. however to answer your question it should be black = ground, red = 5v, and white = signal. from what i have read there should only be a slight difference in reading. i am surprised that the GM sensor isn't used more considering that it is half the cost. guess it is all about ease of install .

 

I would basically also use the GM, nonetheless I had the Defi from another project, so it could be worth using it and not letting it get dust on the shelf


Moreover if I want to use the GM, I have to drill an hole in the manifold, which I don't like too much.

mlocatel

 

how many bar is the sensor (what does the gauge go upto??)

if its 3bar do this:

hook up the power/ground like normal then use a DMM to measure the signal (just at atmo pressure)

if its about 1.5v then its 5v... if its 4-5v then its as 12v...

I suspect it will be 5v... in which case you can just hook up the signal wire to the ECU and it will work ok...

 

Hello Dave

it is actually a 2bar sensor. I'm not sure that this will be enough, but I do not have extreme mods (no FP, no E85)

I'll try like you suggested

Thanks

mlocatel

 

2bar on the display?

so 3bar atmo

let me know how u go

 

Yes
next weekend I'll wire it into the ECU


mlocatel

 

Hallo Dave

I installed the sensor with the 5V as source

it seems to be working. At idle is giving me 0.7 bar. I'm using the JDM MAP scaling as available in Evoscan-

Thnks for the help

mlocatel

 

So you will need to work out the scaling

So just log the RAW value in EvoScan (ie remove the formula and leave 'x') (rpm=0 of course)

Then report back and ill try and work it out for u

 

Hello Dave

I sent you an E-mail with the logs

mlocatel

 

interesting. 2bar is about 29psi right?

i would like to learn more about this!

 

Yes

btu anyway tephra was right: the sensor is good for 0-3bar (2 bar boost)

As soon as either myself or tephra have the right scaling we'll put it there

 

what did u use as a 5v source?