Motor wont start. ECU needs replacing ?

[Cordy1]

Hello I'm writing on behalf of a friend who's been told by his French boat yard that his fourwinns day cruiser is not fixable Following a flat battery, the cables were crossed when jump starting. Smoke and flame observed.
Before giving up I thought I would try this forum to see if anybody can help with the following questions.
The Ecu unit is definately broken.
1) Can the ECU be tested ? Might a Volvo penta agent have a test rig?
2) Is there a diagnostic connection?
3) Does the ECU hold a memory of problems?
4)What other components could have been damaged and might they harm a new ECU if we replace it?
5)What manual would you recommend?

I should that the motor engine turns over perfectly well with the starter but wont fire
Year of boat 1998
Engine Volvo penta 4.3di

 

[spannerman]

Not sure what a 4.3 di is? If its got a carburettor then there is no diagnostic socket, if its injection there should be one. The ECU can’t be tested, they either work or they don’t. If its a carb engine then you need to test for a spark at the plug if there is none then the ignition module is most likely damaged. If its injection then you need someone with a Vodia tool to plug in and see if there is any communication with the ECU, again you can test for a spark and injector pulse if you know your way around feul injection systems. The other thing that may well be damaged is the alternator, but you won’t know until you get the engine running.

 

[springer]

Ho Cordy, sorry to hear of friends' plight. If engine is Throttle Body Injection. i.e. It has what looks like a carburettor which has 2 built in injectors the it is Volvo MEFI type. ECU for these may not be available through VP. If it is still available UK costs in region of £1300.00 + VAT.

There is a MEFI magician in California who can reprogramme, fix, or supply replacement ECU for these type of engine. pm me for details, I have these at work and can send after the weekend.

If engine is more modern multi point injection then VP have withheld all info and the aftermarket guys can't get into these yet.

Springer

 

[Seastoke]

Not sure what a 4.3 di is? If its got a carburettor then there is no diagnostic socket, if its injection there should be one. The ECU can’t be tested, they either work or they don’t. If its a carb engine then you need to test for a spark at the plug if there is none then the ignition module is most likely damaged. If its injection then you need someone with a Vodia tool to plug in and see if there is any communication with the ECU, again you can test for a spark and injector pulse if you know your way around feul injection systems. The other thing that may well be damaged is the alternator, but you won’t know until you get the engine running.

just a question ,about the ecu if its made up of all electronic components why cant a good electronic repair company replace the damaged parts.

 

[petem]

just a question ,about the ecu if its made up of all electronic components why cant a good electronic repair company replace the damaged parts.

They're often tamper proof, sealed and filled with epoxy stuff.

 

[Beamishken]

Probably the best option would be to find someone replacing a complete engine and buy the harness & ecu etc together. A fairly popular engine so maybe worth checking with a few dealers see if anyone has a bust engine languishing in the corner of their workshop

 

[philld]

just a question ,about the ecu if its made up of all electronic components why cant a good electronic repair company replace the damaged parts.

My experience is with automotive not marine ECUs, but I don't think there would be too much difference. The ECU will be an embedded microprocessor board. If the board is fried, the one component that can't be replaced is the microprocessor. It is most likely a custom design, and if it isn't it won't be an off the shelf component. Normal practice is for the software to be written directly into the processor chip. The only people who have access to the code will be the OEM, and they will not hand it out, they don't want people modifying it and creating warranty claims.

Now my personal mea-culpa, I did this last year on my boat :redface-new: Fortunately, I only blew 7 fuses, a relay, and the alternator. I repaired the relay, replaced the fuses, and bought a new alternator, and everything was as good as new. Though my engine is a bit too old for an ECU all the other associated electronics survived. All the smoke and burning smells came from the alternator, everything else was fine. I wouldn't be surprised if the ECU has protection circuitry built in to prevent damage due to reverse voltage, it's expensive enough, and these sort of accidents happen often enough to warrant it.

 

[Cordy1]

Not sure what a 4.3 di is? If its got a carburettor then there is no diagnostic socket, if its injection there should be one. The ECU can’t be tested, they either work or they don’t. If its a carb engine then you need to test for a spark at the plug if there is none then the ignition module is most likely damaged. If its injection then you need someone with a Vodia tool to plug in and see if there is any communication with the ECU, again you can test for a spark and injector pulse if you know your way around feul injection systems. The other thing that may well be damaged is the alternator, but you won’t know until you get the engine running.

 

[Cordy1]

Not sure what a 4.3 di is? If its got a carburettor then there is no diagnostic socket, if its injection there should be one. The ECU can’t be tested, they either work or they don’t. If its a carb engine then you need to test for a spark at the plug if there is none then the ignition module is most likely damaged. If its injection then you need someone with a Vodia tool to plug in and see if there is any communication with the ECU, again you can test for a spark and injector pulse if you know your way around feul injection systems. The other thing that may well be damaged is the alternator, but you won’t know until you get the engine running.

Hello Thankyou very much for your message. I have no idea as I'm just a humble Engmish teacher relaying and translating the information but I will pass your advice on . Thanks very much again