mikuni MK30 red light malfunction

niccapotamus

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we've just fitted a second hand MK30 to our boat (well a chap did the worst of the fitting - i'm far too old to go crawling around the arse end of the boat)

the MK30 worked well on a test bed but we ran it last weekend - it was fine initially for hour or so and then the red malfunction light came on and it won't go away. I wondered if it was our battery but it doesn't make a difference whether it is on the domestic or engine battery or even when the engine is running.

anyone got any fault finding suggestions please? luckily the weather is getting warmer but i'd like it reliable by autumn :)

cheers

nick
 
MK30? I will assume MY30, inside the separate ECU there is an LED, this will flash a number of times to indicate the fault, you should be able to see it through a little window but if not the cover is easily removable, just a single Phillips (not Pozi) screw. The flash code is usually printed on the ECU cover.
 
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MK30? I will assume MY30, inside the separate ECU there is an LED, this will flash a number of times to indicate the fault, you should be able to see it through a little window but if not the cover is easily removable, just a single Phillips (not Pozi) screw. The flash code is usually printed on the ECU cover.

thanks David - it is the one you benchtested for me (we were bidding on it on Ebay)

cheers Nick
 
Don't bother I just remembered your model doesn't have the flash codes, check the diagnostic flow chart (as previously mentioned) on the mikuni UK site. http://www.mikuniheating.com/images/diagnostics/MY30_fault_finder.pdf

thanks. looks like I have to reset it as the first port of call - I think I am probably at "if the top trip has failed the supply has probably been cut whilst the heater is running - reset" on the fault finding chart. I'll follow the electrics through to try to find the trip - a consequence of not doing the fitting myself !!!
 
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Have you checked the obvious, is fuel getting through? Is there enough fuel in the tank?
My Mikuni flashes red when the fuel supply stops - which is when the main diesel tank gets down to 1/4 full as the heater diesel pipe stops 1/4 the way up the tank.
Just a thought.
 
thanks for the thought Habebty. the diesel tank was lowish so it could be that as we are in need of a bit of a top-up. Until i finish making my dipstick I can only roughly guesstimate how much fuel is in the tank!!

David - I'll email you if that is OK

cheers

Nick
 
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