Description

Use this board to test the MegaSquirt’s inputs and outputs on the bench, before you install it on a car!

The JimStim features a microcontroller which allows the simulation of up to 30 different toothed wheels, in addition to the standard distributor signal of the standard stimulator. Instead of having the Megasquirt set to “Stim for Wheel” to test your RPM input on the Stim, you can tell the JimStim to provide a signal like the one from a Neon, Miata, Subaru, most Fords, and many more. It can also drive ignition input mods with pull-ups.

We also included a set of user-configurable jumpers that let you wire it to test IAC motor outputs, spare inputs, and spare outputs. You can wire these up with the selection jumper wires. There is also a bank of screw terminals that let you connect things other than a standard Megasquirt to the JimStim. So if you’re looking for a Stimulator to test out your Microsquirt, MS3-Pro, or other Megasquirt devices that don’t have the standard DB37 connector, you can wire one of these up to a JimStim to test it out.

The current firmware allows you to connect the JimStim to a laptop using a special cable, FTDI part number TTL-232R-3V3. This is not needed for regular operation, but lets you set the wheel pattern and output speed to display via TunerStudio, and allows you to program in custome wheel patterns or make the JimStim sweep its RPM output. As most users will never need this cable, we currently do not stock it, but could add it if there’s enough customer interest. Right now it can be ordered from Digi-Key under part number 768-1015-ND. If you’re interested in seeing these added at DIYAutoTune.com, please let us know!

To power your JimStim, we recommend our 12 volt Stimulator power supply.

You can find the JimStim documentation and assembly instructions at this link.

Note: Below pics are of the final product after assembly, the part# JimStim-K is in kit form. Includes three jumpers as shown in the photo (colors may vary). We sell a 10-pack of additional jumpers if you need more for testing more inputs and outputs.

Product FAQ

What applications call for a JimStim, and when can I use a regular Stim instead?

• The regular Stim can be used for installs when you are using just fuel control, a simple distributor, or a Ford EDIS ignition. The JimStim can do all that plus simulate missing toothed crank triggers, distributorless ignitions, and test considerably more inputs and outputs. We recommend using the JimStim if you anticipate that you might need any of these capabilities.

Can I connect a JimStim to MegaSquirt systems that do not have a DB37 connector, like a DIYPNP or MicroSquirt?

• This is a bit more involved than testing a regular MegaSquirt, but you can make an adapter harness that either connects to the DB37 or the screw terminals, using the appropriate plug for your ECU on the other end.

Can the JimStim be used for non-MegaSquirt ECUs?

• Yes, we have had customers use it for other aftermarket and OEM controllers using adapter harnesses. We cannot promise that its outputs will be exactly what your system requires. Contact us if you need support for a non-standard application.

What is the JimStimX?

• The JimStimX is an add on to the regular JimStim to allow testing MS3X outputs. See the JimStimX documentation for details.

I’ve seen mention of an FTDI cable. Do I need one of these?

• The FTDI cable is only used for very advanced features like uploading custom wheel patterns. Very few users will need this.