JimStim 1.5 MegaSquirt Stimulator with Wheel Simulator – Assembled
JimStim 1.5 MegaSquirt Stimulator with Wheel Simulator – AssembledJimStim 1.5 MegaSquirt Stimulator with Wheel Simulator – AssembledJimStim 1.5 MegaSquirt Stimulator with Wheel Simulator – Assembled

JimStim 1.5 MegaSquirt Stimulator with Wheel Simulator – Assembled

5 out of 5 based on 2 customer ratings
(2 customer reviews)


In stock

SKU: jimstim-c Categories: , , , Brand:

Product Description

DIYAutoTune Part# JimStim-C

This is a newer version of the stimulator, designed by James Murray (jsmcortina on the forums) that expands on the original stim’s features. The main improvement comes with the addition of 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.

The improvements don’t stop there. James added 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, eMS-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.

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

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

This one is fully assembled and ready to go. It includes three jumper wires like the ones shown in the picture. If you need more for additional features, order our 10-pack of extra jumpers.

Power supply requirements:

  • 1 – 9V battery or a DC adapter meeting the following specifications:
    • 12 volts
    • 300 mA or greater
    • P5 plug
    • Center positive polarity

2 reviews for JimStim 1.5 MegaSquirt Stimulator with Wheel Simulator – Assembled

  1. 5 out of 5


    Awesome product! Ordered this one assembled. Nice soldering work done.
    I am using this stimulator to simulate a 4/2 CAS on a 4G63T DSM/GVR4 ECU. So much easier writing code at home than out in the garage burning fuel, and freezing my hands off in the winter, or doing 100’s of WOT pulls just to get something right in the code that requires going way up in the RPM range. This neat little device does all that for me. Plus so much more! :)
    This device can be made to work as a stimulator for many OEM ECU’s out there. You still need a eprom emulator to write code.
    Thank you DIYautotune for providing these great products!
    Yours, Kim H. From Sweden, Europe.

  2. 5 out of 5


    Absolutely wonderful product that is very fun to play with. Besides that it has so many useful purposes when diagnosing ECM and sensors. Don’t know how I worked without it.

    Add to that the wonderful sales and tech support from DIY Auto Tune and it’s a win win!

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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.

Where is this unit assembled?

  • We assemble them in-house here in Suwanee, Georgia, USA.

What sort of warranty does this have?

  • It has a one year limited warranty against manufacturing defects.

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.