How to log a 0-5V source in MPSCAN / MPSCANDROID?

[acannell]

I actually need to do this! My questions are:

-where do I connect the 0-5V source on the ECU
-will this work on an SBEC-T1 (1990 daytona 2.5 turbo)
-will it work in MPSCANDROID

The source I will connect first will be the AFR voltage output of my innovate wideband.

But I also plan on logging other 0-5V things like pressure sensors and who knows what.

This would be EXTREMELY useful. Is it up and running??

[acannell]

So I take it this is not a possibility? I swear Shel-game mentioned several times that MPSCAN could somehow log AFR from an innovate, etc..

[shackwrrr]

Inside of the turbonator cal's there is a built in wideband to narrowband converter. The point is to hook your 0-5v signal from your wideband to the factory o2 sensor input wire. You then set up the voltage conversion table to match the afr output of your wideband setup. The computer takes in the 0-5v signal, stores it in memory (you then can access this in mpscan), the number is pumped into the table where it figures afr based on the voltage, it takes that afr value and pumps it into another table where it determines what the narrowband equivalent output would be then uses that for closed loop operation. I have been running this setup for some time now and it works great. The most work you need to do it the wiring and setting up the voltage table.

[shackwrrr]

To log other 0-5v sensors you would need an open input, intake air temp is a common one as some setups are not IAT dependant. You can also hack the SBEC board and use the battery temp input as another but some custom code would need to be used to block the ecu from setting faults and to be able to log the input.

I don't have any e-85 stations around here but I wanted to use a ethanol sensor hooked to the battery temp input and use it to modify fuel and timing on the fly for the exact mixture of ethanol.

[acannell]

Inside of the turbonator cal's there is a built in wideband to narrowband converter. The point is to hook your 0-5v signal from your wideband to the factory o2 sensor input wire. You then set up the voltage conversion table to match the afr output of your wideband setup. The computer takes in the 0-5v signal, stores it in memory (you then can access this in mpscan), the number is pumped into the table where it figures afr based on the voltage, it takes that afr value and pumps it into another table where it determines what the narrowband equivalent output would be then uses that for closed loop operation. I have been running this setup for some time now and it works great. The most work you need to do it the wiring and setting up the voltage table.

thanks for the info. this is the only way? I thought shel-game mentioned some extra or unused input on the ECU that could be used to connect the wideband 0-5V to. Id rather not put my unreliable innovate wideband in the O2 control loop.

Hmm thats an idea..theres gotta be some unused sensor that we could use as an input for the 0-5V, that already has an ECU ram location. What about "battery temperature"? Why not trick that into reading a 0-5V?

Or what about inputs that are electrically present on the ECU and have a ram location, but are not used on our cars? Like diesel inputs?

Looking at my OTC2000 data line card, I see some candidates:

-battery temperature
-throttle body temperature
-DIS crank/DIS cam status
-water in fuel (diesel)
-battery volts
-throttle body temperature
-throttle body volts (listed separately from TPS volts..not sure what this is)

Could any of those be used as inputs for a 0-5V signal, perhaps with a little conditioning circuitry?

[acannell]

okay I was typing while you responded

I might be okay with getting a fault as long as it doesnt affect the cal. It would only be for tuning anyways.

Depending on how the 0-5V is "conditioned" it might be possible to vary the AFR signal into a region where the ECU actually does not see a problem and trigger a fault, depending on the input. Maybe..

[shackwrrr]

I'd be interested in finding out about those other inputs. The SBEC might have some open ones but Im on an SBEC and i'm not sure what all it has.

[acannell]

I'd be interested in finding out about those other inputs. The SBEC might have some open ones but Im on an SBEC and i'm not sure what all it has.

Okay lets break this down now.

Our IDEAL input would:

1- have an existing ram location in the ECU that is accessible by MPSCAN with no code changes, and is updated at the same fast rate as other inputs

2- be connected to a wire that is accessible somewhere on the vehicle (versus digging into the ECU board)

3- not cause a fault regardless of its value

4- not be used in the ECU for anything important

So...we could start looking up the 60-way connector pinout and see if any signals are listed that we clearly don't use..like throttle body temperature or throttle body volts. And if that pin has a wire, we can find it and give it a voltage and see if MPSCAN picks up the change in voltage. And voila! Maybe we get lucky and its that easy!

And this process would apply to any ECU. Look at your particular ECU pinout and see if any signals are definitely not used by your cal, and see if you can manipulate it and see that in MPSCAN.

[acannell]

rats..looking at my pinout I dont see anything that isnt very important and used

hmm

I wonder if its possible to put something on the internal vehicle body computer bus, that the ECU can query? If we added a little module with a MCU, that had a bunch of inputs, is there some way to get the ECU to query it for values or something?

Or maybe the body computer has inputs?

Theres an "oil level input" and "transmission pressure sensor" ..maybe those could be hijacked?

There has GOT to be a way to get a 0-5V signal digitized by the ECU and read out by MPSCAN.

Maybe it would make more sense to look at all the known ram locations on the ECU and eliminate all the ones that are clearly important and see what we're left with?