Wiring short blowing unswitched breaker

[Byron Biggs]

So below is my problem and symtoms.

Symptoms

Could not start stb engine (turned over without issue, port eng started)

<br />Stb unswitched breaker was popped and repeatably popped every time tried to switch to on position

<br />Smell of burnt insulation and very slight smoke

<br />Did not have a lot time to troubleshoot, going down (boat 75 minutes away) to boat this AM with elec schematics.

<br />My interpretation of the schematics says the stb unswitched breaker feeds system monitor (which I have never found, dont believe I have), cabin stereo memory, control station switch, fwd bilge pump, aft sump pump, control station switch, aft bilge pump, fwd emergency pump, emergency bilge pump, eng sync, blower controller line 1, blower controller line 2, plus at the bus bar (believe the one in main dc breaker panel in eng room. All of the above comes of of plug 17 drawing 09-601 (5 of 5) rev 3 EXCEPT eng unswitched bus bar drawing 09-601 (4 of 5)

<br />Will check eng room components and wires(if i can find) from above and hope i find something other than one to eng (assume this if bad means ECM).

Update: Looked at wires by device for all pumps and blowers and saw no charring.  Checked voltage for port eng and got 29.2 V(this i did not understand. was expecting 12v, where is 12v to 29V converter (transformer)?).  Checked voltage for Stb eng and got 22V (had someone switch on breaker and chk voltage before breaker tripped).

<br />If anyone has any direction or past experience it will be appreciated

Topic

[Byron Biggs]

i screwed up

Please ignore original post.

I now believe the problem is a short in the ecm power cable.  Investigating this weekend.

Thank you

[Author]

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