MEFI 3 Datastream Definition

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Captain Brian
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Joined: Sat Jan 31, 2015 1:28 pm
Location: Detroit
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MEFI 3 Datastream Definition

Post by Captain Brian »

Guys, I am looking to read the engine parameters such as RPM, Coolant, and Fuel flow from my MEFI 3 engine controller, does anyone have the datastream definition files for it?

I don't want to modify the cals I just want to look up the data so I can put it on the canbus of my boat.

Any help would be great.
cbernhardt
Posts: 95
Joined: Fri Apr 18, 2008 5:19 am

Re: MEFI 3 Datastream Definition

Post by cbernhardt »

Captain Brian wrote:Guys, I am looking to read the engine parameters such as RPM, Coolant, and Fuel flow from my MEFI 3 engine controller, does anyone have the datastream definition files for it?

I don't want to modify the cals I just want to look up the data so I can put it on the canbus of my boat.

Any help would be great.
OBD Diagnostics (http://mefitune.com) sells a definition file that is used with the older version of ScannerPro. This will allow you to monitor and data log all of the MEFI3 parameters. Not sure how you would interface with CANBUS.

Charles
roughneck427
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Joined: Fri Feb 20, 2015 12:09 pm

Post by roughneck427 »

I have a TTSdatamaster for the MEFI3 it was a beta version I called them and they gave me a free license I used my LT1 cable with a couple jumper wires for the grd and serial data
Captain Brian
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Joined: Sat Jan 31, 2015 1:28 pm
Location: Detroit
Contact:

Post by Captain Brian »

Roughneck, thanks for the info, did your MEFI 3 system have the old rectangular diagnostic connector or the new "modern" OBD - II connector. Mine is a marine application that has a unique 10 pin diagnostic port. Any pictures or drawings of how you connected to your MEFI and the jumper you describe would be great! Thanks again!
roughneck427
Posts: 2
Joined: Fri Feb 20, 2015 12:09 pm

Post by roughneck427 »

Captain Brian wrote:Roughneck, thanks for the info, did your MEFI 3 system have the old rectangular diagnostic connector or the new "modern" OBD - II connector. Mine is a marine application that has a unique 10 pin diagnostic port. Any pictures or drawings of how you connected to your MEFI and the jumper you describe would be great! Thanks again!
I emailed you the info my boat has the 10 pin Delphi connector I purchased a male connector and made a crossover harness to an obd2 style using my moates aldu1 cable. all it is is two wires I emailed you the data sheet I have
Espy
Posts: 1
Joined: Tue Feb 14, 2023 4:50 pm

Re:

Post by Espy »

roughneck427 wrote: Sat Feb 21, 2015 10:55 am
Captain Brian wrote:Roughneck, thanks for the info, did your MEFI 3 system have the old rectangular diagnostic connector or the new "modern" OBD - II connector. Mine is a marine application that has a unique 10 pin diagnostic port. Any pictures or drawings of how you connected to your MEFI and the jumper you describe would be great! Thanks again!
I emailed you the info my boat has the 10 pin Delphi connector I purchased a male connector and made a crossover harness to an obd2 style using my moates aldu1 cable. all it is is two wires I emailed you the data sheet I have
Roughneck427, I have a similar application (marine), I have a twin engine boat (2000 Mercruiser 7.4L MPI) that uses the MEFI-3 ECMs, one of the ECM was blown and I have gotten a replacement one that needs to be reprogrammed. So, I was wondering if I could use the TTSdatamaster software to read and copy the existing file of the good ECM and download it into the new ECM or if there is a way to get a file that I can use to download to the new ECM (as I was told that the file in the good ECM is locked and I would not be able to copy it).

Also, could you provide me as well with the pictures/drawings of how you connected your MEFI system and the jumper you used.

Any help and/or suggestions would be greatly appreciated.

Thanks,
Espy
pattiflemi
Posts: 1
Joined: Wed Nov 01, 2023 9:50 pm

Re: MEFI 3 Datastream Definition

Post by pattiflemi »

I can access some ECM data including fuel gph & gals/used for port & stbd and total gph & G/U for both engines, plus eng hours, rpms, coolant .
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