Howdy folks. With the ever increasing popularity of the MM3 tuner, I'd thought it would be a great idea to make a trouble shooting help guide. With any product, there can be common issues and hopefully what I mention may help. These suggestions also apply to the RaceME Ultra or Smarty Touch as well. Feel free to add to this post with any helpful ideas.
First and foremost take your time assembling the unit and installing it. Parts are small and fragile. I've had many customers plug in cords backwards, install SD cards backwards, snag and pinch cables, etc... by simply not paying close attention to what they were doing. Look at connections carefully and don't force things together. Most parts fit only one way. If doesn't seem to fit right, well it probably isn't.
When installing your tuner let the OBD connection be the last thing your plug in. Theses tuners have 3 CPUs and they must all communicate when you plug the power source in which is the OBD connection. Failure to do this will cause the tuner not to work.
Well what if you install everything correctly and it does not work..
If your display shows no signs of life when you turn on the key on, check you micro USB cable connections. If they are loose, it won't work. Remember these cords are much like a phone charger cord and can't take being pulled and tugged on. I've had customers plug these cords in upside down and damage the female ports in the main CPU unit and display. If you spread the female port from such a mishap, you can take a small pick or screwdriver and tighten up the receptacles.
If you suspect your cable is damaged, you can easily run out to the local electronics store and buy a new cable. You most likely won't find a micro USB with two male ends, but can buy adapters to make a cable that will work.
If you turn on your key and the display flashes the green and red lights with no picture...then you have an SD card problem. You will either need to reformat or replace your SD card. Remember if you reformat your card, you will be erasing all data on it...so save the .ecm and .rtg files that I've installed on your SD in the custom folder before hand to your PC. Reformat with the FAT32 format. Reinstall the latest update for the MM3 on the SD card next. The update files for the MM3 can be found here... http://mm3power.com/downloads/ Next paste your ecm and rtg files back into the appropriate folders. If you start with a new SD card, use the same procedure.
Most are connection related. Make sure the J1939 unlock cable is installed. I don't know how many guys I've had not install this cable at all or remove it after the initial flash. This cable must be plugged in for the tuner to write the ecm or change the tuning via the RT menu.
Another big connection issue that really throws a monkey wrench in are OBD splitters. DO NOT write your ecm through an OBD splitter. I know OBD splitters are common with the use of AMP power steps. You are best to hard wire AMP power steps and not connect them via the OBD if you are gonna use a tuner like the MM3.
Another thing. If your MM3 warns you the voltage is low for programming...don't program! Charge your batteries first! Low voltage programming can really jack up your tune!
If you get a message when you program that says something like "ver mismatch" or "unknown calibration"...this means the MM3 doesn't recognize the operating system of the current calibration as being compatible with what you are attempting to program in. If this happens, you will most likely have to purchase a recovery calibration ($120 available thru me) to flash in to change your current operating system to one that is compatible.
These are just a few highlights that I thought were common enough to mention. Many more things could occur and if they do, we can find a solution. Hope this post does help.
Double R Diesel, LLC