Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > Sport Touring: ST4 / ST3 / ST2 > duff electrics

[wayned]

Well I waited 'till next payday to find myself swamped by bills , so putting the bike on the dealers mathesis tester will have to wait again.

When turning on, the pump doesnt prime, the relays click (I've tried a new one anyway to no avail), the starter turns the engine fine.
I'm hoping to save a bit of cash and test what I can myself (dealer charges £57/hour). I would like to test the pump and the reg/rectifier but have no electronic tools to do so. Does anyone have an idea what I should buy and how to go about testing these components ? And is there anything else I could have a look at.
I have a copy of the manual but as far as testing goes it just mentions a mathesis test.

[Jools]

Hello mate,

Whip the fairings off and make sure all the relays are clean and free of corrosion (and all the other connectors too).

There are two big obvious relays near the ECU, but there are others of the little buggers up by the headlight. My ST showed just those symptoms in the car park of the cat & fiddle and it turned out to be the sidestand switch relay (left hand side of headlamp). It could also be something quite stupid like the kill switch corroded and not making contact and thinking it's off - oh no, starter wouldn't turn then would it, but you get my point.

Basically, just clean up any connectors you can and see if it helps

[Shazaam!]

I don't have a wiring diagram, but the fuel pump circuit should be fused, probably through the engine management relay in-line fuse. Check for a blown fuse or corroded fuse connector clips. A dirty fuel filter will blow the fuse.

[HW]

If you think it's any help .. I have a complete wiring harness for an ST2 (3k miles) so there are all the connectors, relays etc. Only ECU missing. You could do worse than get some silicone spray, but if the pins in the connectors have gone green you might struggle to get them cleaned up. Let me know if you need any bits.

[John W]

There is a 3 amp fuse up in the fuse box to the left hand side of the headlights. If that is blown it gives exactly the symtoms you describe.

You get to this by removing the left hand side clock trim (2 screws).

[wayned]

I'll have a check round the loom tomorrow ..hopefully its a duff connection as the fuses and fuel filter are all ok.
Cheers for the advice

[wayned]

Now I've had some time, I've checked all the electrics (contacts - no greenstuff, fuses etc) no problems found. Cut the fuel filter open and it looks pretty clean. Bought spare relays and swapped old ..no problems again.
1 thing I have noticed , after turning the key and flipping the killswitch initially both relays under the seat click but on flipping the killswitch more only one operates (whilst not turning off the ignition with the key).

A mechanic at the local moneygrabbers recons the relay thing is weird and informs me in his opinion my ECU has died.. "but hey they only cost £856"... *COMMENT CENSORED*.

If noone else has any ideas I think I may go and lose the bike in a skip. (ok, ok but it is tempting).

The mechanic also stated its not simply replacing a us ECU with another and that they recquire programming to match the clocks (?) (I say mechanic loosely here). If this is true what about vice versa (I replaced a set of broken clocks about 7,000 miles ago and have also found a 2nd hand ECU for £100. If it will go straight on I may try that first before a dealer visit)

[Edited on 9-5-2005 by wayned]

[Edited on 9-5-2005 by wayned]