2015 Volvo d2-55 mdi

[Sunharvester]

So mine has failed. I can see the capacitors inside have blown their lunch. Waiting for a dealer to fix. In the meantime I installed a start button inside the companion way cabinet. 

I wired it to the batt and starter connectors on the mdi.  I also moved the mdi off the engine. In the Hope's the new one might last a little longer

[Salty]

Sorry, but what is an “mdi?”

[symphony2]

Little black box that links the mechanical diesel engine to the Volvo electronic control panel on D1 and D2 series engines. Has been troublesome for many users and most replaced under warranty or a recall. Not a great bit of design as attached close to the exhaust manifold where it suffers from vibration and heat which fries the non repairable electronics. Some people have installed a work around such that you can still start the engine and stop it with the mechanical fuel stop on the injector pump.

Had no problems with mine, but replaced under a recall. side effect is it zeros the engine hours as they are calculated in the electronics.

[Yngmar]

The problem is/was so bad that some new production boats came with starter bypass buttons installed by the yard. 

[Salty]

Okay, thanks Symphony and Yngmar. Looking up the meaning of the abbreviation or acronym came up with a list of 86 possibilities, and even the individual explanations didn’t really shine much light in a direction that would enable being able to select the correct meaning.

[Sunharvester]

Volvo Penta has an active quality campaign(recall) to replace this little black box that sits just above and behind the alternator.

There is no good reason to attach it to the engine but yet there it is. 

The supposed reasons for failure are vibration and heat affecting electrolytic capacitors or over voltage greater than 13.8v that one would get from a solar charger.

The failure often presents as intermittent.  So sometimes the start stop control display works and sometimes not in varying forms.  Wont start, wont stop, erratic fuel level readings. Etc.