Newbie with MEFI 4b and questions.

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lonewolf41
Posts: 5
Joined: Mon Aug 28, 2017 5:58 am

Newbie with MEFI 4b and questions.

Post by lonewolf41 »

I have a Volvo Penta with the MEFI 4b ECU. I would like to read parameters, codes, etc. Not interested in changing anything right now. My understanding is that tunerPro will allow me to do this. From my reading, it appears that I need an ADX file to tell the software how to interpret the data from the ECU and have it display on the PC. Is that correct? I also need some kind of cable to connect the computer to the diagnostic connector on the boat. I know I can buy one from mefiscan, but I am wondering if I can make my own. Does anyone know what kind of cable the mefiscan cable really is? I suspect it is just a USB to RS232 converter, but that is just a guess. Anyone know if that is true and has anyone made their own cable?

I am tempted to take a USB to serial converter cable and put the correct 10-pin connector on it and plug it in to the boat, but and leery of doing that before I have conformation or at least more info.

TIA for helping out someone just learning this stuff.

-Keith
cbernhardt
Posts: 95
Joined: Fri Apr 18, 2008 5:19 am

Re: Newbie with MEFI 4b and questions.

Post by cbernhardt »

lonewolf41 wrote:I have a Volvo Penta with the MEFI 4b ECU. I would like to read parameters, codes, etc. Not interested in changing anything right now. My understanding is that tunerPro will allow me to do this. From my reading, it appears that I need an ADX file to tell the software how to interpret the data from the ECU and have it display on the PC. Is that correct? I also need some kind of cable to connect the computer to the diagnostic connector on the boat. I know I can buy one from mefiscan, but I am wondering if I can make my own. Does anyone know what kind of cable the mefiscan cable really is? I suspect it is just a USB to RS232 converter, but that is just a guess. Anyone know if that is true and has anyone made their own cable?

I am tempted to take a USB to serial converter cable and put the correct 10-pin connector on it and plug it in to the boat, but and leery of doing that before I have conformation or at least more info.

TIA for helping out someone just learning this stuff.

-Keith
You can read the data from the MEFI4a with the older ScannerPro program, change the parameters with the older TunerPro, but you will need the MEFIBurn program to read/write the tune from the controller.

To use ScannerPro you will need an ADX file for the MEFI4a.

The newer TunerProRT which allows you to monitor the data, modify the tune, and also read/write the tune will not communicate with the MEFI computers, at least I have not been able to make it work. There are several posts on this forum on this subject.

Before I purchased the USB cable from Mefiscan I made a serial cable to communicate with the MEFI controller using ScannerPro. I don't think I have the cable anymore, so I can't give you the pinouts.

Charles
lonewolf41
Posts: 5
Joined: Mon Aug 28, 2017 5:58 am

Re: Newbie with MEFI 4b and questions.

Post by lonewolf41 »

cbernhardt wrote:
lonewolf41 wrote:I have a Volvo Penta with the MEFI 4b ECU. I would like to read parameters, codes, etc. Not interested in changing anything right now. My understanding is that tunerPro will allow me to do this. From my reading, it appears that I need an ADX file to tell the software how to interpret the data from the ECU and have it display on the PC. Is that correct? I also need some kind of cable to connect the computer to the diagnostic connector on the boat. I know I can buy one from mefiscan, but I am wondering if I can make my own. Does anyone know what kind of cable the mefiscan cable really is? I suspect it is just a USB to RS232 converter, but that is just a guess. Anyone know if that is true and has anyone made their own cable?

I am tempted to take a USB to serial converter cable and put the correct 10-pin connector on it and plug it in to the boat, but and leery of doing that before I have conformation or at least more info.

TIA for helping out someone just learning this stuff.

-Keith
You can read the data from the MEFI4a with the older ScannerPro program, change the parameters with the older TunerPro, but you will need the MEFIBurn program to read/write the tune from the controller.

To use ScannerPro you will need an ADX file for the MEFI4a.

The newer TunerProRT which allows you to monitor the data, modify the tune, and also read/write the tune will not communicate with the MEFI computers, at least I have not been able to make it work. There are several posts on this forum on this subject.

Before I purchased the USB cable from Mefiscan I made a serial cable to communicate with the MEFI controller using ScannerPro. I don't think I have the cable anymore, so I can't give you the pinouts.

Charles
Thanks for the response. I have the cable pinouts so I am good there. Since all I am interested in is reading data (had an oil pressure switch go out on me this weekend and would have made troubleshooting much easier), where would I get a copy of the older Scannerpro software that works with this ECU? I did not see it in the downloads section. Also, I have searched everywhere for an ADX file and have so far come up empty. Any idea where I might find that?

Thanks again!!
cbernhardt
Posts: 95
Joined: Fri Apr 18, 2008 5:19 am

Re: Newbie with MEFI 4b and questions.

Post by cbernhardt »

lonewolf41 wrote: Thanks for the response. I have the cable pinouts so I am good there. Since all I am interested in is reading data (had an oil pressure switch go out on me this weekend and would have made troubleshooting much easier), where would I get a copy of the older Scannerpro software that works with this ECU? I did not see it in the downloads section. Also, I have searched everywhere for an ADX file and have so far come up empty. Any idea where I might find that?
Thanks again!!
As far as I know the only source for the ADX file is OBD Diagnostics.
https://obd2allinone.com/mefiscan.asp
A copy of ScannerPro comes with an ADX file.
lonewolf41
Posts: 5
Joined: Mon Aug 28, 2017 5:58 am

Re: Newbie with MEFI 4b and questions.

Post by lonewolf41 »

cbernhardt wrote:
lonewolf41 wrote: Thanks for the response. I have the cable pinouts so I am good there. Since all I am interested in is reading data (had an oil pressure switch go out on me this weekend and would have made troubleshooting much easier), where would I get a copy of the older Scannerpro software that works with this ECU? I did not see it in the downloads section. Also, I have searched everywhere for an ADX file and have so far come up empty. Any idea where I might find that?
Thanks again!!
As far as I know the only source for the ADX file is OBD Diagnostics.
https://obd2allinone.com/mefiscan.asp
A copy of ScannerPro comes with an ADX file.
When you say "A copy of ScannerPro comes with an ADX file", do you mean it comes with the one I need or it comes with a generic one?

Thanks.
cbernhardt
Posts: 95
Joined: Fri Apr 18, 2008 5:19 am

Re: Newbie with MEFI 4b and questions.

Post by cbernhardt »

lonewolf41 wrote: When you say "A copy of ScannerPro comes with an ADX file", do you mean it comes with the one I need or it comes with a generic one?
Thanks.
As far as I know, when you order the scanning software you get a copy of ScannerPRO and the appropriate ADX file for your MEFI controller. Call OBD Diagnostics and ask them.
Charles
lonewolf41
Posts: 5
Joined: Mon Aug 28, 2017 5:58 am

Re: Newbie with MEFI 4b and questions.

Post by lonewolf41 »

cbernhardt wrote:
lonewolf41 wrote: When you say "A copy of ScannerPro comes with an ADX file", do you mean it comes with the one I need or it comes with a generic one?
Thanks.
As far as I know, when you order the scanning software you get a copy of ScannerPRO and the appropriate ADX file for your MEFI controller. Call OBD Diagnostics and ask them.
Charles
OH, OK. I thought you were talking about the free version, not the paid version. I think I have found a 4b file that I can try with the free version to see if my cable works.
GaryDoug
Posts: 5
Joined: Tue May 07, 2013 4:58 am
Location: Florida

Post by GaryDoug »

I don't have any experience with the MEFI4 files, but I can tell you that the MEFI3 adx file will NOT work with TunerProRT without some modifications. I think that the ScannerPro version may have some procedures hard coded into it and those are not executed in the adx file. Adding those steps back fixed it for me. It could be a way of protecting the files from being used on a free app like TunerProRT. For example, the adx file did not have the read commands being executed in the file, just the request commands. The fix was to change the file to the macro groups for each (Silence and Data Read) instead of just requests. Also, the adx file did only one Silence command and it needs at least three in quick succession. My copy of ScannerPro would work with the supplied adx file but was extremely flaky with the data jumping all over the place until I fixed the file by adding 2 more silences.

May I ask where you found that 4b file? I would like a copy if possible.
Author of Scan9495 (apps for LT1 and L32 F-cars) and MEFI3-Scan
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