System Fault STBD 521-20. ??

2019 Merc 250 pro xs v8.
2B596875 is serial
model is 250LPXSTM
76 hours
Basscat Lynx
24 Fury 4



smartcraft tack beeps and said “system Fault 521-20”

was just scanning an area at 5-600 rpm when it went off. I shut it down for a few min. Started back up and it seems ok.

can you tell me what the code means? I think it got hot. When I turned on temp was like 197 and came down when I started idling around. Drove 15 min and no more warnings. Maybe trash or something plugged intakes......where can I find out what the system Fault 521-10 means?

thanks

According to this link, I would be lead to believe it is an overheat alarm. Start at page 90.

https://www.dropbox.com/s/lvrfcpf9qo...anual.pdf?dl=0

+1... Overheating.

Unless you are certain of the cause, you may want to get this checked carefully. One look at the exhaust section of this engine and you should be able to understand why you do NOT want to be overheating the engine (there are a number of hoses, plenty of wiring and some plastic components in that area of the engine).

Did you find the cause of this alarm? I just had the same fault happen to me yesterday. I check the vessel view and temp was high(190). I shut it down till it cooled back down to 130 and tried to start it again. Temp then continued to rise. I turned it off and got towed back the the ramp.

water was still coming out of tell tale while it was alarming and I check 2 strainers and they were clear. I have suspect a pump problem and have heard of the gaskets being installed wrong. I just bought the boat used in February from a dealer and they said the pump was changed along with the oil.

Mine was a bad impeller/water pump. Replaced and never happened again

Quote:

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Originally Posted by Ramos27

Did you find the cause of this alarm? I just had the same fault happen to me yesterday. I check the vessel view and temp was high(190). I shut it down till it cooled back down to 130 and tried to start it again. Temp then continued to rise. I turned it off and got towed back the the ramp.

water was still coming out of tell tale while it was alarming and I check 2 strainers and they were clear. I have suspect a pump problem and have heard of the gaskets being installed wrong. I just bought the boat used in February from a dealer and they said the pump was changed along with the oil.

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If you would, please take a moment to review the Announcements at the top of the Forum, and be sure to provide the Required Info (serial number) when you post.

Also- please open a SEPARATE thread for your engine (one engine per thread to avoid confusion and/or post hi-jacking). Thanks! :beers:

Good rule of thumb: ANYTIME you have overheating and/or low water pressure problems, ALWAYS, ALWAYS start AT THE SOURCE: The Water Pump.