ECU disconnect on 2006 GRiSO 850

Bike was driving perfect,parked in dry shed.Was left about 4 weeks,started once or twice no problems.Last week put 2 new brake discs on front,when turned on ignition to bring for test drive,oil,neutral,etc lights flash on and off,red triangle light stays on at top right hand side of dash and at bottom ECU with a plug and socket disconnected is showing,never came across anything like this before,what would be the problem ??

Not a good sign. Usually that symbol, unless you are up or downloading a map,indicates the ECU has bricked itself.

First things to check though are the earth connection from the body of the ECU to the loom, (Make sure it has continuity to earth as well as just being tight.) and then pull the plugs on the ECU itself and check pins and connectors for corrosion or breakage.

Pete

It means ECU & dash not connected (no communication). Do what Pete suggests. It could also be the dash connectors.

Had the connectors off the ECU,look clean and dry in there,would ECU pack up like that just from sitting there ? Only thing had look in owners booklet and says to remove 30 amp fuse in front of battery if not using bike for 2 weeks or more,bike not been started in about 3.

No, sitting won’t cause a problem. The reason they suggest pulling the 30A fuse is simply to stop the parasitic drain from the immobiliser.

Pete

Happened to me some times - usualy with weak batery. Haven't seen it since I relocated the main earth wire to a different bolt on the motor.

Yea battery was down alright,charged it up but made no difference,put a new battery out of another bike in it too,same.Tried earth it different places too with jump leads,I ll try earth lead from battery to somewhere else on engine.Never had this bother with a bike before,Italian electrics are famous for something.

Have you checked continuity between the ECU body and the motor using a multimeter?

Something Pete had mentioned in his earlier post, the ground wire at ECU. I have found on more than a few G's that the ring terminal to ground has a bad crimp and some the wire can be pulled out by pulling on it. Just a light crimp will cause the dash to show a disconnect even though it looks ok.

Fully charged battery battery overnight,same thing ECU disconnect on dash,what a heap of scrap,maybe thats why not many guzzis aronnd anymore,anybody want parts or swap/p/x for a decent Jap bike ? sorry I know probably wrong place to be saying this but these bikes a total crap.

Did you check continuity to the ECU ground as Steve & Pete suggested? Not just jumper it, but actually confirm it's a real ground? Did you reseat the dash connectors? Charging the battery won't fix it.


Find the speedo sensor connector. Check for 12V on the red/black wire when you switch the key on. If there's 12V there when you switch the key, and you have confirmed the ground, then there's a good chance your ECU is fucked.

Would the ECU go just from being parked for few weeks,not driven,in a dry shed ? Only thing done to bike was front wheel was removed and new brake discs fitted,calipers also removed and refitted,bike was jacked up couple inches.

I would like to say "no", but in my experience 90% of electronic failures are at power-on. By design, an automotive ECU is a hardy piece of kit, and therefore I still think some weird shit is going on. Don't give up just yet. It's possible something obscure has occurred.

You want to bitch about the bike but won't confirm anything. If you are not, take it to a dealer who will.

Nobody bitching here,facts are as stated/confirmed,bike parked 3 weeks,when switched on to start it,lights,oil,neutral etc flash on and off and ECU with plug and socket disconnected on display.Dealer maybe 100 miles away if there is even one in Ireland,I would gladly pay someone to fix it so I could get rid quickly.

Look my friend,people are trying to help you here, in case you aren’t able to comprehend it, from thousands of km away and in the case of some of us half a world away! Via the internet!

Yes, I don’t doubt it’s frustrating but we can’t help unless you ANSWER THE FUCKING QUESTIONS!

If your ECU has shat the bed there will be a reason. We’ve said the most likely causes and asked for you to check shit. Easy shit that can be done with a test light or cheap $10 multimeter. So far you’ve given no answers and just carry on like a chook with its head cut off! How old are you? Twelve? Get a fucking grip man!

Even if it has shat the bed ECU’s are cheap enough but you have to find out WHY yours is on the fritz so you can fix it before you put the next one in. If that is all too much effort you don’t need a Honda you need a bloody bus pass!

Critters anyone??
Maybe a rat chewed up something while the bike was sitting...
Happened before and will again.
Machinery doesn't like to sit too long.

The ECU is under the steering head between frame tubes, I believe there is a cover under it. Pretty easy to get to.

Plastic cover retained by two button head screws that screw into speed nuts on the frame. Take it off and the ECU is revealed. The earth wire goes to an 8mm headed hex bolt on the body of the ECU. Use a multi meter or test light to check for continuity to earth after ensuring the earth wire hasn’t pulled out of the eyelet on the end of the wire.

Pete

I think we're wasting our time gents. He's been a member for 5 whole days, and wanted us to fix his bike via osmosis or somesuch, then sell it.


I've lost interest.

Seems to be becoming more common. Same thing just happened on the Mana board. Some dood has the ‘Service’ warning and ‘Gear’ appear on his dashboard and asks what’s up. Explain that it’s probably the variator threads sticking and that there are numerous threads on the issue and to do a search. That wasn’t good enough. He wanted to ‘Know how to fix it’. Presumably a step by step, with pics, run down as the numerous previous explanations or the belt replacement photoessay I’d already done that is pegged at the top of the page wasn’t good enough.

Life

Is

Too

Short

I ve had the ECU off,connectors look clean and dry,earth was also there,cleaned it with wire brush anyway,also put a new earth line on battery,I dont have a multimeter.Have other bikes parked in same shed and all start fine.

Also seen ECUs on Ebay for other Guzzi models,look the same as the one in GRiSO,would they be the same ?

It’s not the ECU per se, it’s the map that’s in it. There are a host of W5AM ECU’s from Guzzi’s and some Ducati’s that will work but they need to have the correct map in. Anyway there is no point, zero, in fitting another ECU until you find out what caused the other one to fail, if indeed it has failed. It is obvious you are fathoms out of your depth here. Find someone who knows what they’re doing and let them fix it.

I would compare numbers under barcodes anyway.Yes its out off my dept alright,pity as fine bike to drive,plenty power.Is there a mercury tilt switch on them ? only thing can think of even though bike was not jacked up much to remove front wheel while doing discs.