# megasquirt and easy therm



## TURBOCADDY (Jan 17, 2002)

I tried to make my bosch sensors read correct using easy therm and now i cant connect to the ecu 
i have a ms v3 setup for wasted spark running a 1.8t using factory sensors for coolant and air temp 
i got the car to start and now am not able to communicate with the ecu 
has anyone experienced this?


----------



## CanadianCabby (Sep 1, 2006)

*Re: megasquirt and easy therm (TURBOCADDY)*

talk to matt at diy


----------



## need_a_VR6 (May 19, 1999)

*Re: megasquirt and easy therm (CanadianCabby)*

When you loaded the code did it count past 1700 lines and then pulse the fuel pump? I would try and reload the firmware in any case.


----------



## TURBOCADDY (Jan 17, 2002)

*Re: megasquirt and easy therm (need_a_VR6)*

will try reloading firmware today


----------



## [email protected] (Sep 8, 2008)

*Re: megasquirt and easy therm (TURBOCADDY)*

It could be you used the wrong S19 file for EasyTherm. The directions for it can be confusing, so here's a set I wrote up myself:
When you open EasyTherm, there will be several options you need to set. It defaults to GM sensor calibrations. On our ready-made units, you will leave the bias resistor value set at 2490 ohms; you'll only change this if you have opened the Megasquirt and swapped out the resistors.
The boxes in the middle of EasyTherm are where you enter the sensor calibration data. You will need the sensor resistance at three temperatures. You can obtain this from a factory service manual or simply by testing the sensors in boiling water, ice water, and water at a measured room temperature. The sensor needs to be what's known as a negative temperature coefficient thermistor. This is simply a fancy engineering word for saying the resistance goes down as the temperature goes up.
Next, you need to select the code version. You'll set it to "Custom" for MSnS-E firmware such as 029v. Leave the start address alone. Then you get this information into the code by clicking "Write .inc and .s19 Files." It will prompt you to open an S19 file containing the code. Select the file that corresponds to the MSnS-E version you are using. If you do not have a copy of the MSnS-E firmware, you can download it here:
http://www.msextra.com/manuals...x.htm
EasyTherm will generate four files. One is an S19 file that will have the same name as the original with "_mod" added to the end of the file name. The other three are .INC files for MegaTune. Their names are airdenfactor.inc, matfactor.inc, and thermfactor.inc.
EasyTherm can load the S19 file into Megasquirt, too. Power down the Megasquirt, open it up, and put the boot jumper in place. Then connect it to the computer and power it up, ideally on a Stimulator. If you power it up on a car, disconnect Megasquirt from any coils or ignition modules it may be connected to. Then specify the COM port where you have Megasquirt attached and click the "Download to MegaSquirt" button. EasyTherm will prompt you to select the S19 file you need; it will be the one that ends in "_mod" that you've just created. It will then download your newly calibrated firmware. Shut down the Megasquirt, remove the boot jumper, and close its case back up.
If you had the firmware you started with in the same folder as your car project, it will automatically put the INC files in the right place. Otherwise, you'll need to copy them so that MegaTune will be able to correctly interpret the sensor data. The default location for these files is in the EasyTherm folder if you have altered a firmware copy in the EasyTherm folder. They go in the mtCfg folder in your project folder. If the project was named car1 and you have the usual folder setup for MegaSquirt, for example, you would want to copy the INC files to this folder:
C:\Program Files\MegaSquirt\car1\mtCfg
Once you've got that taken care of, you will have your firmware uploaded and MegaTune will know what to expect. This takes care of your sensor calibration.


----------



## DieGTi (Jun 19, 2001)

*Re: megasquirt and easy therm ([email protected])*

I just finished a firmware upgrade to hr11c2 and Easytherm did not behave as described above when loading the bosch sensor values. 
1) Open EasyTherm program.
2) Select "Bosch Defaults" from file drop-down menu.
3) Select "Hi-Res" from code version list on EasyTherm4f main screen.
4) Click "Write .inc and .s19 Files"
Upon completion of Step 4 above, the message field on the EasyTherm main screen displays "Output Complete...".
Navigating to the Easytherm folder, C:\Program Files\EasyTherm will produce 6 files:
1) airdenfactor (INC File)
2) EasyTherm (CC File)
3) matfactor (INC File)
4) megasquirt.s19 (S19 file) - only 14kb file size, far smaller than 77kb S19 file currently loaded to ecu.
5) megasquirt_HR.s19 - only 14kb file size
6) megasquirt_HRmod.s19 - only 14kb
Following the firmware uploading procedure, jumping the boot loader and cycling as prompted by EasyTherm produced a non-responsive ECU. 
I solved this by uninstalling and reinstalling the Easytherm program on my laptop. I then went to my firmware folder, c:\program files\hr_11c2\src and selected the file "msns-extra.s19 file. I copied this file and pasted it to the directory c:\program files\easytherm. and I then deleted the existing "megasquirt_hr.s19" file, the 14kb one, from that folder. I then renamed "msns-extra.s19 that I pasted to this Easytherm folder to "megasquirt_hr.s19" as Easytherm would not function once it's original file path was missing. I then ran the following steps again:
1) Open EasyTherm program.
2) Select "Bosch Defaults" from file drop-down menu.
3) Select "Hi-Res" from code version list on EasyTherm4f main screen.
4) Click "Write .inc and .s19 Files"
This time, the megasquirt_HRmod.s19 file that Easytherm produces and dumps into c:\program files\easytherm is 77kb. 
Following the firmware uploading procedure, jumping the boot loader and cycling as prompted by EasyTherm produced a functioning ECU. I then manually copied the three .inc files from the c:\program files\easytherm folder to the project folder for this setup, c:\program files\megasquirt\12v_vr6 .
Completely different but worked for me when nothing else would...


----------

