MEFI ADX Connection Problem

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iaff284
Posts: 4
Joined: Tue Aug 18, 2015 4:54 am
Location: Champaign IL

MEFI ADX Connection Problem

Post by iaff284 »

Hey All,

I am having issues with Tunerpro RT connecting to an MEFI 3 ECM. I am using a custom cable that I have made using an FTDI 232RL to USB board and a custom plug to connect to the DLC. I have the TX and RX from the FTDI 232RL device attached to the Serial output of the DLC. The ground from the DLC is connected to the ground for the FTDI 232RL. When I connect the device to the DLC and turn the ignition on and acquire data with the MEFI 3 .adx open, It says connected, both the TX and RX lights on the FTDI 232RL light up and stay lit but the dashboard on Tunerpro does not respond. The connection icon show connected but the mhz stays at 0.03 but no data is displayed. I have updated to the latest version of Tunerpro RT and updated the FTDI driver to the latest version. I have tested the FTDI device using Realterm and can connect to the device and what I type shows up on the screen indicating that the device is connected and functional. I googled the serial number on the FTDI chip and it did not come up as a fake. I can open Tunerpro click on acquire data and and test the cable and it shows as connected and functional. The only thing I can figure at this point is that there is possibly an issue with the commands in the .adx or with the .adx file itself. Any help is greatly appreciated!!
iaff284
Posts: 4
Joined: Tue Aug 18, 2015 4:54 am
Location: Champaign IL

Post by iaff284 »

So I did some more checking today and the connect command had a mode 8 stop chatter command in it instead of the command macro. I changed that and now when I make it connect the connect icon will flash blue and say connected and then flash red and say error and start counting errors. It will do that until I make it disconnect. The connection speed will initially show 0.5Hz and then freeze. I have looked at a bunch of different adx files for 95-96 5.7 pcms and have tried several command macros and they all do the same thing. Anybody have any ideas?
iaff284
Posts: 4
Joined: Tue Aug 18, 2015 4:54 am
Location: Champaign IL

Post by iaff284 »

Anybody???
cbernhardt
Posts: 95
Joined: Fri Apr 18, 2008 5:19 am

Post by cbernhardt »

I asked a similar question several years ago:
http://forum.tunerpro.net/viewtopic.php ... highlight=

Are you trying to modify the tune in the MEFI3 or just wanting to scan the outputs? Most of the MEFI tunes that I am familiar with (the GM RamJet engines) are password protected so that they cannot be downloaded without the password.

You probably know this, but ODB Diagnostics sells scanning software for use with the older ScannerPro and TunerPro programs and their MEFIBurn program for up/downloading the BIN files.
hamhock75
Posts: 12
Joined: Thu Jul 13, 2017 2:01 pm

Post by hamhock75 »

Just a thought. I am new to this myself and just was able to get the Tuner ProRT software working with my L82 engine.

The first thing I checked was what the voltage levels are from the DLC. I understand it can be 0-5 volts or 0-12 volts. 0-5 volts is TTL levels which the USB to Serial TTL adapter can talk to but if it is 0-12 volts, it won't. It might test as working only because the TX out to RX in of the adapter is just talking to itself but not the DLC signal.
GaryDoug
Posts: 5
Joined: Tue May 07, 2013 4:58 am
Location: Florida

Post by GaryDoug »

You can get a free copy of a MEFI3 adx file that works with TunerProRT. The one that comes with ScannerPro will not work without modifications.

http://www.mediafire.com/file/mc8on8qyv ... rproRT.adx
Author of Scan9495 (apps for LT1 and L32 F-cars) and MEFI3-Scan
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