[2013 Stelvio 1200 NTX ABS] The start-up maintenance relay (4 on the wiring diagram) and main injection relay (30) both have back-emf protection diodes on the coils. I bought a replacement start-up maintenance relay from Gutsibits (item ELA82462) which, a bit to my dismay, has no quenching diode on the diagram on the casing and was (for a relay) horrendously expensive. Similarly this Stelvio has a bog-standard four-pin relay in the main injection relay socket. The Gutsibits item (ELA81869) looks different in that it has a white relay base.
Can anyone confirm that not having the back-emf diode on the start-up maintenance relay (or the main fuel injection relay) will not cause problems? Alternatively, does anyone know where I can get the correct start-up maintenance relay for -erm- somewhat less of a cash outlay?
This is not my Stelvio. I was asked to take a look at it because I specialise in rewiring motorcycles. I told the owner that I couldn’t guarantee a fix because I’m not familiar with the large small-block engines. However, after fixing a lot of bodges in the main loom (and with a lot of help from posts on this forum) I nailed the initial ‘ECU disconnected’ error to be a genuinely dead ECU. It was replaced and the dashboard lit up and self-tested correctly. Having unexpectedly got this far, I’m very reluctant to hand the bike back with a possible timebomb lurking in the wiring.
I got my replaement relay for a CARC from the local car bits shop - took the old one in and they noted the DIN numbers and gave me a replacement - it has a diagram moulded in showing the diode!
Also, just for info, if it had a dead ECU the only two cases of that i have heard of (one was mine) was after very very heavy rain so i think that the waterproofing around the two ecu plugs may degrade over time?
This was causing an intermittent triangle of doom and non starting, using a standard relay allows diagnosis but the diode is to allow the Ecu to health check.
Can’t remember where I got a genuine replacement from.
Add another one A very heavy rain shower down near Dublin followed by an unexpected excursion through a deep puddle. Everything’s been cleaned with contact cleaner and the relays have been reseated with dilectric grease. I did think about putting dilectric grease on the dashboard and ECU connectors too, but as it relies on the terminals pushing through the grease layer and I don’t know what the ECU/dashboard female terminals look like, I skipped that idea.
I suspect that some ECUs (all bikes) may have failed through overheating or PCB cracking too.
The white patches on the leftside and rightside are very heavy aluminium oxide patches. Forgive me if I’m teaching granny, but the ECUs are a two-part assembly; the ECU and a heatsink. In the pic the heatsink is the lower bit (I’d already part cleaned it). The oxidisation was forcing the ECU away from the heatsink to the point I could see daylight through the gap. To me, that provides the potential for overheating. The ECU part also had a distinct bend in it which (possibly) could put stress on the PCB.
Thanks Brian. I’ll get one from Gutsibits, check the diode number and see about converting some ‘ordinary’ relays for ‘stock’. Rumour has it that the owner of this Stelvio knows another one that is misbehaving .
Errr… you won’t believe this… I have three relays arriving probably tomorrow, direct from Mandello del Lario. The owner of the Stelvio is Italian and he knows somebody who, it turns out, knows one of the factory mechanics. They’re even being shipped express!!!
I did check with Gutsibits but they don’t keep OEM relays as fitted to the NTX in stock. The lead time is at least three weeks.
A very heavy rain shower down near Dublin followed by an unexpected excursion through a deep puddle. Everything’s been cleaned with contact cleaner and the relays have been reseated with dilectric grease. I did think about putting dilectric grease on the dashboard and ECU connectors too, but as it relies on the terminals pushing through the grease layer and I don’t know what the ECU/dashboard female terminals look like, I skipped that idea.
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