I have seen numerous postings about MMC (now ZF) MicroCommander Problems on Mainships and thought I would clarify the most common problem I find with the installation of these controls. My company is Control Masters Marine Systems and we are the top US distributor of ZF Mathers Engine Controls. I have been installing and servicing these controls for over 30 years so my back ground is very extensive.
I installed the first MicroCommanders for Luhrs Mainship at their plant in St. Augustine. These were installed using a 10 amp breaker for each MicroCommander, to power up the MicroCommander you turned on the breaker (simple and safe). When Mainship began installing these units themselves they installed an ignition relay (if your controls power up when you turn on your key or activate the ignition circuit then you have a relay). This relay is the number one issue I have seen and corrected on the Mainships as the relay can fail causing the power to the processors to be lost.
What I do and recommend to all Mainship owners with electronic controls is to rewire the MicroCommanders to 10 amp breakers and eliminate the ignition relay, this will solve about 90% of the control problems on the Mainships.
The other thing to keep in mind is the control head (lever you push to shift and throttle) is a wearable item and over time may need to be replaced. Under normal conditions they will last 15 years or more. Those exposed to the weather may not last as long as it all depends how they were installed.
I have also noted where some believe the MicroCommanders may be causing their engines to shut down. That cannot happen with the MicroCommander as the main things these controls do is provide a neutral safety interlock if you try to start in gear, shift the transmission, increase or decrease throttle, and provide auto synchronization on twin engine vessels. They do not control engine shut down and even if you turned off the power to the controls the engines will keep running.
There are over 100,000 vessels with the MicroCommanders worldwide (including Navy vessels and Coast Guard Vessels). These are very reliable controls when installed and maintained properly.
If you have a question or problem I am always available to provide tech support on these controls via email or phone call. Our phone number is 904-260-9756 and email is email@example.com
Just a note My motor yacht has ZF MicroCommaders on it as well and we travel all over the Bahamas without any concern.
Have a great boating day!