Hi all, I’ve got a 05 749, and the last couple of months I’ve had numerous issues starting the bike. Typically it’ll turn over, fuel pump primes but the bike won’t start. Then after a few tries the fuel pump will cease priming. The first time this happened I switched the battery out for a new one, no change, I played around with some of the fuses by the headlight, pulled the one closest to the dash display and when I replaced it, the pump primed and the bike started up fine. It’s been run occasionally since then, and it’s always on a trickle charger. Then on Friday, went to start the bike, fuel pump primed, bike turns over but doesn’t fire up, after a few tries fuel pump ceases to prime. I take the battery off, disconnect the ECU, check the fuel pump relay, check the ECU earth, all look ok. Replace and the bike fires up again. I’m at a loss as what to fix. I figured I’d get a new fuel pump relay as they are cheap, but is this a sign my fuel pump is on the way out, my ECU on the way out? Any suggestions would be appreciated!
If you get studying the ignition related circuits, there are a few items worth checking, I see you have replaced one relay, there is a second one but can’t remember if it’s ignition related. Also, is your ECU Earthed ok? Be on the lookout for small signs of corrosion on any connector pins, particularly the relays and fuses. Are you storing the bike in a slightly damp atmosphere? For the future: – If intermittent pump priming is your only symptom, then it is worth looking at the wires that pass through the pump housing body, as this is another weak link and covered on here two or three times fairly recently.
https://www.ducatiforum.co.uk/threads/2006-749s-fuel-pump-not-priming.41315/ https://www.ducatiforum.co.uk/threa...a-heart-attack-on-the-replacement-cost.31060/ https://www.ducatiforum.co.uk/threads/749s-fuel-pump-not-priming.45415/page-3 https://www.ducatiforum.co.uk/threads/749-fuel-pump-not-priming.81146/page-2
I'd start by checking the kill switch (this s=isolates the fuel pump to kill the engine) and side stand cut out switch...
you're right, I checked, it's the same tiny relay which you can swap to test if bike starts which is probably what threw me.