Engine Comm Error - Thoughts

[aich75013]

My 2016 AR190 was having an Engine Comm Error and the tach would sweep back and forth the entire time.
I dropped the boat off and had it looked at. Was told the speed sensor was bad and needed to be replaced. It was on back order, so I took my boat back so we could use it until it was shipped.
We used the boat this summer. No issues other that the tach/speedometer not working, but we installed a Lowrance Hook 4 and used that for speed.
Dropped the boat off this Tuesday and they replaced the speed sensor. No luck.
Today they replaced the tach. Still didn't help.
They said they took parts from a new boat to see if replacing them would fix the issue (to help diagnose the issue.)
They are saying the boat may have been struck by lightning and that may have fried something in the computer. They are keeping the boat next week to try to diagnose further.

Thoughts?

 

[aich75013]

Update.
Dealer was able to find the problem.
There was some corrosion where the engine wiring harness connected to the fuse box. The dealer ended up needing to replace the engine harness, fuse box and ECM.
Odd issue, but I thought I would update in case anyone has a similar issue and can't figure it out.

 

[Jgorm]

Struck by lightning. Lol. That translates to we have no idea what we are doing.

 

[pete4180]

I can't start my AR190, engine won't turn over, on board computer won't light up. If I keep the key in engine start position the computer lights up and I get Engine Com Error. You let go the key and everything goes out. I'm getting 12V from the battery, I'll try to charge the battery and clean the terminals to see if it helps.

 

[pete4180]

Problem solved! Turns out that I forgot to connect second negative cable to the battery. After quick fix it started right away without any problems, no errors.

 

[KyleP]

I’ve done the same. Forgetting that 2nd ground caused and corrected the error for me lol

 

[Irvs]

These engine ECUs are picky with the voltage they sense......Most of the time the engine comm error is due to poor battery post to the terminal itself. You should just clean the battery connections or get yourself new connectors every year.

 

[d4davis]

This post saved my A$$....2 different dealers reps told me that I had a serious issue "engine comm error" and to load up the boat and leave it with them for a few weeks....after reading this, I checked to make sure the guy who replaced the battery attached both black cables....he didn't....problem solved....Thank You!

 

[Gunner]

When I remove the battery for the winter I tape all the negatives together so I don't forget one in the Spring. When you get older you have to do shit like that because your brain turns to mush.

 

[jetlagged]

Similar to the original post, my 2010 AR240 did either suffer a lightning strike or a serious power surge - it fried my pool control motherboard, my boat lift control box, and the extension cord I had running from the dock power to the battery charger was blown apart. Anyway, when I turn on the battery switch (2 battery system), the alarm sounds and I am not able to silence it. Both engines start and run, but the left tach needle cycles between min and max constantly: the readout is “Eng comm error”, and the digital tach readout is only a dash ( - ). The right tach reads normally.
I disconnected and reconnected both batteries, the contacts are clean and tight, and the battery voltage on both reads at least 12.5V.
mid anyone has any advice, I’m all ears.

 

[jetlagged]

Similar to the original post, my 2010 AR240 did either suffer a lightning strike or a serious power surge - it fried my pool control motherboard, my boat lift control box, and the extension cord I had running from the dock power to the battery charger was blown apart. Anyway, when I turn on the battery switch (2 battery system), the alarm sounds and I am not able to silence it. Both engines start and run, but the left tach needle cycles between min and max constantly: the readout is “Eng comm error”, and the digital tach readout is only a dash ( - ). The right tach reads normally.
I disconnected and reconnected both batteries, the contacts are clean and tight, and the battery voltage on both reads at least 12.5V.
mid anyone has any advice, I’m all ears.

I want to add that the boat has not run for a couple of months and nothing was done to it since it last ran (except for the electrical “event”), and it has run perfectly since I bought it new. I checked all known fuses and everything appears normal.

 

[jetlagged]

I want to add that the boat has not run for a couple of months and nothing was done to it since it last ran (except for the electrical “event”), and it has run perfectly since I bought it new. I checked all known fuses and everything appears normal.

I also swapped the two ECU’s, no change.