Alarm wont turn off and engine wont start

[ksethman]

I mistakenly posted this in the wrong section so am posting in the correct one, sorry.

Hi All,

Been reading tons of topics but cant quite seem to find one that fits so I am hoping you can help. Here is the history...

I bought a Larson 2002 LXI 210, mercury 5.0 MPI, gen 2 outdrive to months ago. Had it inspected by a third party, all service done and impeller replaced. I have had it out 2 times, first time all was good, stalled once at idle but started right back up, The second time was out all day, was we were heading in and going through a no wake zone the engine died and would not start again.

The boat had not been used a lot in the recent year or 2 so I hoped it was just water in the fuel seperater, changed it (filled with fuel) but no luck. Being a first time boat owner I figured it was good time to "get to know a mechanic".

3 weeks later, they have no idea what the issue is, fuel pressure is good, spark is good, nothing seems to be wrong but it wont start. They tried hooking it up to a diagnostic tool but for some reason they wont talk to each other. They think something electrical or the ecm (?) and are verifying all electrical first. They think it could be a bad wire or something.

Baically if turn the key on the beep is delayed for a minute or 2 instead of as soon as turned on, then the alarm and fuel pump turn on. The alarm does not turn off and the pump turns on and off.

Anyone have any ideas what could be causing something like this?

Thanks for any and all ideas!
Keith

 

[dubs283]

Re: Alarm wont turn off and engine wont start

could be simple as a bad battery/connections all the way to a bad ecm

load test the battery, check all connections including grounds - clean and tight??

wiggle test on the wiring harness and relays - could be a broken wire casing grounding out somewhere

check connections at the ecm

do you know what type of diagnostic program they are using?? rinda, diacom, cds, ddt??

 

[ksethman]

Re: Alarm wont turn off and engine wont start

funny you say that, it just sparked my memory, the first time I went to look at the boat, I could not test run it as it had an alarm issue, the owner paid the marina to fix, they said it was just a low battery. They charges and load tested and all was fine, the alarm issue went away. Funny part is there was 2 batteries in the boat but only one was hooked up. I wonder if the marina mistakenly switched the batteries "fixing the issue". I added a dual bat switch the day before this, maybe having both batteries hooked up and grounds connected is now causing the issue because one battery is defective, seems odd that it happen right away but who knows...

I think he said Diacom and the ECM was model 555

Thanks!!!!!!!

 

[Don S]

Re: Alarm wont turn off and engine wont start

Low battery will give a continuous alarm, and if too low the engine won't start or crank.

Hook up one good battery directly to the engine to get the engine problem isolated. Then you need to determine how to wire good batteries up correctly in your boat.

You shop sounds like they just got their Diacom, but no one knows basic troubleshooting before you hook up a diagnostic tool.

 

[ksethman]

Re: Alarm wont turn off and engine wont start

They tried hooking up a separate battery but no change, cranks but wont start.

I was mistaken, they are using a rinda techmate and purchased the adapter but are not getting any information back from the ECM. They say all the wiring is good, sensors are good, etc. They say its all pointing to the ECM. I guess it kinda makes sense since it wont communicate with the scan tool? do these things go bad often? Really sucks that I just bought the damned thing and 2 trips in having to cough up 2k+ for all this

I found a used one for 500.00 on ebay (they say is tested and good) and new ones are running 17-1800.00. I just had a computer rebuilt on my car, does anyone rebuild these for boats?

odd question but shouldnt these things be basically a black box, all the ones I see online are a plug in what looks like a flat piece of metal.

ECM is 555-0202, part # 864271-3, 884521

 

[Don S]

Re: Alarm wont turn off and engine wont start

No, they don't fail that often, but they do fail on occasion.

I wouldn't buy one off ebay. There is too many versions of the 555, and only 1 will work on your engine, and you can't test one off the boat. They just want your $500. No warranty I bet, and no returns.

odd question but shouldnt these things be basically a black box, all the ones I see online are a plug in what looks like a flat piece of metal.

They are a black box. that flat piece of metal is actually 2 sheets of metal with electronics in between.

 

[ksethman]

Re: Alarm wont turn off and engine wont start

Thanks so much!

I just spoke to a guy that repairs these, he said it sounds like the crystal (for internal timing) has gone bad, the system starts up can finish its own diagnostic and sounds the alarm, the fuel pump gets the start message but wont turn off as its not getting a second signal due to the clock timings being out.

For 500.00 they will repair if broken and repairable, if it is not broken, they will charge me 100.00 for their time.
the also have new ones for 300 less then anywhere else I can find.

Seems like a win/win scenario, I get confirmation is actually broken and not mechanic issue, repaired if possible or new if required.

Now I just have to pray that it is actually repairable, I only paid 10k for the boat. The part plus unknown labor cost for 3 weeks is going to be at least 20% of the purchase price....

Thanks for assistance Don and Dubs!!