Gen2/Motor Controller/Configuration

The controller's configuration implements a number of Zero features:

• Speed calculations.
• Distance calculations.
• Over-voltage limits to protect the battery by cutting out regen or refusing to operate.
• Under-voltage limits to protect the battery charge state.
• Current limits to protect the battery.
• Delay before regen toggles on or off.
• Driving modes like Eco/Custom/Sport which include speed and torque limits and speed ramping limits to prevent wheel lockup.

References

Sevcon Gen4 product page (formerly at [1])

Gen4 data sheet (no longer available without request form with contact details)

Gen4 reference Manual

Configuration

Some MBB settings direct the Sevcon controller; look to the MBB first.

The MBB can also provide a dump of Sevcon diagnostics and logs.

DVT software to maintain the Sevcon programming is available but recent versions require a license and the cabling is not cheap. The older unlicensed versions may have trouble maintaining newer programming by Zero.

Direct diagnostics

For those interested in better understanding your Zero's motor controller setup, you'll need some specific cables and software.

These will allow you to browse the current controller configuration as well as make changes such as increasing regeneration rates, customising sport or eco modes etc.

This is what you'll need:

1. An IXXAT CAN-USB compact adaptor v1.5 (v1.01.0087.10100) or v1.6

   approx USD300 but you may find it cheaper on eBay or borrow/rent it from another forum member or dealer.

   You cannot buy these anymore, you must get them off ebay or part of a Thunderstruck EV $900 kit.

   You cannot use a new version of the IXXAT CAN-USB either as it will not work with an unlicensed copy of the software. And to get a license you have to own a business.

2. A DB2 female to OBDII male cable with a specific pin mapping (not the most common one).

   Easysync make a DB9 female to OBD male cable that has the correct pin configuration - about USD25

3. Sevcon DVT Customer software

   It has to be version 1.03c or lower to use unlicensed (Google is your friend, as is Dropbox in this case).

   Good luck saving your DCF files with it.

   You need to write down your settings before making big changes.

   Even if you bought the new version and got a license you would have to use a NEW IXXAT USB-CAN as the old one isn't compatible.

   The Sevcon software will run on Windows XP, 7 and 8.

   There are manuals and getting started guides on the Internet (Google again) on how to use the DVT software including one at Thunderstruck EV.

Warning:

Do not link any files as they have been removed multiple times in the past.

• One of the dropbox links you will find will have at least 3 different versions.
• If you install any new versions completely remove everything from the previous versions.
• If you find the program wont start up and it isn't 1.02 then install a "merge" installation of TCL and it should work.

Warning:

You can brick your controller temporarily by making changes.

It would be nice to have a backup but these online versions of "free" sevcon software all have issues with saving.

I have tested 1.00 1.01 1.02 (which never ran) and 1.03c so far.

If you brick your device you will need someone to give you a DCF file to return your device to working order.

But good luck getting it from a form member who doesn't work for a dealer as stated it is next to impossible to export the file.

Sevcon is very much against this use of their product and software, and have issued takedown notices for publicly available files.

You will not get official support and people will be reluctant to post details publicly.

Get the 200 page DVT / SEVCON GEN 4 manual from the manufacture's webpage and read it a couple times.

Try contacting knowledgeable people privately.

You really need to understand what you are doing when you start to make changes.

This isn't a toy you are going to be remotely piloting, it is a vehicle you are risking your life on!

Zero has specific programming to customize the Sevcon controller.

So it is not clear whether customer customization is achievable beyond basic modification of settings or performing an alignment using DVT.

Recovery

DoctorBass has documented a backdoor method of recovering a Sevcon controller if its firmware is in an unusable state

Using the IXXAT connection, issue the following command:

can send "0x7FA 0x48 0x65 0x79 0x73 0x6c 0x69 0x70"

This byte sequence is also apparently available as "BD" (for "backdoor", presumably).