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ECU Diagnostic Software

OBD2 Type FIAT with JP Diag


** A license is NOT required if your bike uses the IAW59M ECU (usually applies to 2001-2004 Ducatis)

1. USB VagCom 409.1 KKL lead (the software will work with ELM327 and Galletto but KKL is preferred)
2. Fiat Adaptor
3. Cable Drivers (Either FTDI driver or Winchiphead driver depending on KKL cable type chipset)
4. Software - JP Diag



For the USB cable recommendations are to obtain FTDI driver based ones.  However, Winchiphead driver based ones will work after modification described below.  The two different type cables can be distinguished by plugging in to the USB port.  FTDI will not illuminate its LED, Winchiphead will illuminate its LED.   Also, the two fly lead Fiat Adaptor is preferred but the single (red) fly lead version will work. When you get your adaptor continuity test the fly lead. There have been instances of the wrong colors being put on the crocodile clips. The red fly lead must terminate at pin 16 on the OBDII female plug. The black fly lead must terminate at either pin 4, pin 5 or both.

Cable drivers can be found here:

FTDI (http://www.ftdichip.com/Drivers/CDM/CDM20830_Setup.exe)

Winchiphead (CH341SER.EXE)



Do you definitely have a FTDI based cable?  Again, you can distinguish between FTDI and Winchiphead as the latter will illuminate its LED as soon as you plug it in to the USB port.  If it is Winchiphead then you need the correct driver CH341SER.EXE.

Once the drivers are installed and then the USB cable plugged into your PC, identify the Com Port number for it in ‘Device Manager’ under Ports. A com port number of 1 to 9 is recommended. Use advanced settings to change the com port number if not.

The ECU Software Download here:

Confirm the Com Port number for the lead using Device Manager. Enter the Com Port number in the box on the Software. 

Ducati motorcycles made between 2001 and 2004 are likely to have an IAW59M ECU. The correct setting for the IAW59M ECU is ‘Slow Init’. This ECU does not require a license for the diagnostic software to fully function.

For bikes with the IAW5AM ECU use ‘Fast Init’ and a license is required to fully function. Use the blue copy button in the software and then the request page on the website.


** If anyone does find that they have the Winchiphead lead then you need to do a modification by making a solder bridge between pins 4 and 5. The picture below shows how to.


As you launch JPDiag you will be presented with a screen displaying 3 picture options of your cable setup. Choose which one corresponds with yours when the time comes.

To be safe check your power lead pin out back to your ODB II cable before you connect to anything at all by doing a resistance check with a multi-meter:

You'll see in the picture below the operating pins on the OBDII  cable.

OBDII pin n. 5: Negative;
OBDII pin n. 7: K line (where the data travels to and from the controller);
OBDII pin n. 16: 12V +

Cablaggio diagnosi moto (Motorcycle diagnosis wiring) is the K Line

The pin you need to check is #16, it is positive power so set your multi-meter to ohms and connect one probe to pin 16 and the other to the red alligator clip.  I simply inserted a largish sewing needle into the corresponding female pin hole and connected the multi-meter probe to it to check continuity. Check your negative while you're there too if you like, it's pin #5. Pin #7 is the K line which you needn't concern yourself with.

That's your polarity check sorted. DO THIS BEFORE YOU CONNECT UP TO ANYTHING !!!


At this point you should have installed the correct driver and JPDiag.

Before launching JPDiag connect the cables -

1. Join the OBD and Fiat cables together and plug them into the usb of your computer.
2. Check in Device Manager under Ports which COM port the cables are using. (people suggest using some number 10 or below)   You will need to know the port number in case it needs correcting in JP Diag. DO THIS BEFORE CONNECTING TO YOUR ECU. If you select the device listed under ports and right click, go to properties and in the drivers tab you can check to make sure it's operating with the right driver which should be FTDI if FTDI Based Chipset or Winchiphead driver if other.
3. Connect red alligator to positive battery terminal and the black to a good ground on your bike (negative).
4. At this stage a little blue LED came on in the OBDII cable. I don't know if all manufacturers have this.
5. Launch JP Diag and select your cables.
6. Once the program interface opens you'll see a connect button alongside a field into which you'll need to enter what COM port you're using.
7. Check the ini field setting - IAW59M use 'slow ini' IAW5AM use 'fast ini'
8. At this stage you can do another test on your cables. Set your multi meter to 20v and do as below:

    Click Cable Test -
Connect the +ve and -ve fly leads to a 12v power supply e.g. your bike battery but do not connect the diagnostic plug. Set your multimeter to 20v and connect the +ve lead on the meter to the single outer pin in the Fiat Adaptor. It should look like this [- | - -]. Connect the -ve lead from the meter to the middle pin or the -ve terminal on the power supply.
Click on the connect button and the KLine 12v and KLine 0v tabs should become selectable
Your meter will read in excess of 12v straight away. If you have the correct com port you will be able to click on the KLine 0v and the voltage on your meter will drop to 0.3v. Click on the KLine 12v and the meter will read over 12v.
If you don't get this behavior then the KLine is not working so check your setting (probably Com Port)

9. Now if everything to this point is in order go ahead and connect your Alfa lead up to your ECU.
10. Click the connect button which is near the port # field and you will see on the screen "connecting", I waited a little while then turned the ignition key on and like magic on the left hand side in JPDiag you'll see the basic ECU data. Copy it and post it in the request license form and you'll get a message back from jpl which will include license file. This cle.lic file then needs to be copied into the JPDiag directory .

The pins you will connect to are:
Pin 4 = +12v
Pin 10 = -ve
Pin 16 = K Line
Pin 17 = +12v
Pin 34 = -ve

The side you connect to is where the heat sink screws are closest together

Connection technique also plays a part. Do not connect +12v until you have pressed 'Connect' in the software. Then connect +12v.

**For IAW59M use 'slow init' and IAW5AM 'fast init'


Likely Issues:

1. Did you install JPDiag correctly. Did you click on the computer icon on the second screen of the installation and then follow the prompts?

2. Have you set up the correct Com Port for the cable? Check in Device manager, the lead will show up under com ports. If the com port number is over 10 then change using advanced setting to a lower number.

3. With Win7 you need to navigate to the folder Program Files/JPDiag and locate the file jpdiag28c.exe (the one with the icon of an Italian flag). Right click on this file, select properties, select compatibility and then check XP Compat Mode and Admin Rights. Then click apply.

4. Put the correct com port number in the box on the start screen of JPDIag. For IAW5AM ECU's select Fast Init. For IAW59M ECU's select Slow Init. (IAW59M used up to 2004)

5. With the leads connected to the bike. The +ve fly lead to + on battery, the -ve fly lead to good earth on frame or engine. Click connect. You should see green bar below that box and change to 'Disconnect'. Now turn ignition of bike on.