Ducati.ms - The Ultimate Ducati Forum banner

After disconnecting battery bike won't start.

13K views 30 replies 14 participants last post by  falcofred 
#1 ·
So today I fitted a Stiebel Nautilus horn which needed a direct power connection to the battery +ve and earth to battery -ve so I had to disconnect the battery briefly to make these connections. Apart from that nothing else electrical was tampered with apart from the horn leads being connected to the switching side of the relay.

Reconnected everything disabled alarm meta then pushed red switch to start, got the DTC off message, so switched it back on in the menu, and tried again but all I get is the usual fuel pump priming noise and when I press the starter button no clicks but the fuel pump priming noise with each press of the starter button.

Spoke on phone to Ducati Glasgow running through a few cross checks and they couldn't suggest anything I might have done wrong. So I rechecked all the connector blocks down the offside frame where the new wiring and compressor air hose were routed but couldn't find anything loose or disconnected. Battery terminals all checked and tightened. All fuses checked which I then had to switch on DTC after checking main fuse.

Still nothing when starter button pressed only the fuel pump priming noise!

In the menu I found a battery charge reading of 12.5V so it's now on the battery charger just in case it was a bit low, other than that I'm stumped.

Anyone out there experienced something similar after disconnecting their battery?
 
See less See more
#2 ·
Just had a thought, not used to can-bus electrics, maybe I will try removing the negative relay lead from the battery and connect it to a frame earth point instead.
 
#6 ·
Yup I checked it with it on the centre stand, and also with also clutch applied in case false neutral was showing. Battery nearly fully charged again but going to leave it til morning to try again.
 
#7 ·
Disconnect everything you put on...and try it again.
Does that horn come with it's own relay? Does it have a diode accross the coil? (Should have otherwise the back emf generated can disrupt the CAN a bit but ain't going to stop in from starting).
The horn is a 'can' item but if you have simpy used the wires that went to the oem horn to go to the relay coil....and used new wires to feed power to the relay contacts and new horn and a separate gound back to the battery...then it's hard to see any of that will prevent starting. (Is the horn working? If not, is the relay 'clicking' when you press the horn?)
 
#8 ·
Stiebel horn came with its own relay, Not sure if there is a diode across the coil? The original horn I left connected to the wiring and added new wires from the original horn connectors back to the switching side of the relay. New power feed from battery to relay and ground of horn to bike. Annoying thing is the horn is working perfectly short press of button, original horn gives a short bip, longer press and the Nautilus kicks in too.

Fully charged battery last night just in case battery being low was causing problem, still wouldn't start, then disconnected all the horn leads still nothing. So I guess recovery to Ducati Glasgow is only thing now.
 
#9 ·
So now waiting for Ducati recovery to collect bike to take it to Glasgow Ducati, it's 12.45pm now here's hoping they get here in time to get it to Glasgow before 4pm when they finish today!
 
#11 ·
Bike now on its way to Glasgow, all the normal start-up lights cycled as usual nothing unusual on display, the fuel pump primes, push the start button the fuel pump primes again as long as the starter button is pressed! So on Tuesday (closed on Monday) Ducati Glasgow will give it the once over and probably find the problem easily I hope!
 
#12 ·
The bike is now safely with Ducati Glasgow, thank you to Martin for waiting back for the recovery truck to arrive. On Tuesday investigations will begin.
 
#13 ·
I don't think this adds much (if anything) to this thread, but I've, also, recently added a couple of elec devices to our bike. Before I started, I called the dealer and spoke to one of the mechanics there asking 'if I disconnected the battery would I create a calamity' and he said "NO, but be sure to disconnect the negative terminal first". He didn't say why (and I didn't ask), and I then proceeded to install the first device, using his advice, all without any issues; all worked fine when I was done. A few days later, I got around to adding the other device and (not surprisingly for me) failed to remember his advise and disconnected the positive terminal first...I was just about done when I remembered what he'd told me....and thought, 'well, dummy you've screwed up again', but when I reconnected everything, all was good. So...I'm not convinced it's too important which one is disconnected first, but I don't feel too comfortable about this conclusion as I don't know WHY he made that suggestion. I'm going to ask him next week and suspect that there just might be a good reason.
 
#18 ·
We should have a competition to guess what's wrong!
Gear position sensor...that goes into the BBS and onto the CAN then to the ECU. We should have asked if it was indicating neutral...or suggest he pull the clutch in and try.
Side stand switch...well it it is in neutral that wont stop it starting.
Start/stop switch?
Faulty starter solenoid. I wonder if he checked the big fuse in the solenoid? (We should have asked him if he could hear/feel that solenoid operating).
Interesting. (Yeah....I'm a bit bored tonight!!)
 
#19 ·
Ok in less than an hour the master technician at Ducati Glasgow traced the problem back to the Meta Alarm, Now I hadn't thought about this as it seemed to be arming and disarming correctly and once disarmed the fuel pump was working. I had to move the meta alarm box under the rear seat to drill the hole for the air line, I didn't realise that the alarm leads inside the box had push fit connectors, moving the alarm had loosened one of these enough to disconnect the ignition circuit. Pushing it back properly solved the problem. Now I know this if anything similar happens again it will be one of the first things I check.
 
#22 ·
No the meta alarm wasn't the OEM one, Ducati Glasgow recommended using the meta alarm as it was in their opinion better than the OEM one, same cost so went for it. Now I know how to check the alarm as easily as checking the bikes fuses if something similar happens again, however it shouldn't as I won't need to move the alarm unit again.
 
#23 ·
The reason why the negative lead should be disconnected first on any negative earth vehicle, is that doing so eliminates the possibility of shorting and electronic damage if anything else touches later. Ie. once the negative lead is disconnected, the whole wiring system is 'dead', and unshortable.

If the positive lead is disconnected only, any wire touching the chassis or metal part, will short and spark, which usually results in terminal damage to electronics.

Think of it this way. The flow of electricity is always FROM the negative post TO the positive battery post after it has gone though the electrical systems. So if the negative post is disconnected, that's it, no more electricity can flow anywhere. Its cut off at the source.
 
#25 ·
Fastoy. 'Convention' had 'current' flowing from +ve to -ve. Factually you are correct...electron flow is from cathode to anode. (-ve to +ve).
But...if you have removed the positve wire from the battery...any 'other wire' touching anything is not going to cause a shirt/spark. With the +ve wire removed from the battery...there is no potential difference between any 'loose wires' on the bike and any part of the bike's frame or structure.
I recall from when I first got my bike and studied the wiring diagram, several circuits switch a ground to activate and other switch a positive. Either way...with any one wired removed from thre battery, there is no 'return' path...so operation/short/spark can not occur. (Unlike of course AC mains...where a single live wire can find a 'return' via many routes...and kill you!)
 
#26 ·
Rode to Indy for MotoGP, everything good. Monday morning load the bike to return home, and it won't start.
The battery is strong, the engine turns over, but the engine will not fire up.

My wonderful wife drove 7 hours with my truck to rescue me :)
I'll be taking the bike to Myers Motorcycles in Ashville tomorrow, anyone have any ideas on why the bike would crank, but not start?
 
#28 ·
Falco. Could be one of many things of course...and all not easy to diagnose at the roadside. Do let us all know the outcome. Thx.
(Someone should devise a 'roadside' checklist that enables us to do some simple diagnosis of the fuel and ignition system).
 
#30 ·
Gone are the days when we'd just pull a plug lead off and see if it sparked to ground...and pull the fuel pipe off the carb's and see if we got fuel...ah!!!
Do let us know...hopefully something dead simple! (Mmmm...hopefully!)
 
#31 ·
So I take the bike to Myers. They shoot a little carb cleaner in the snorkel and the bike fires up :eek:
They start it several times, hook it up to the diagnosis tester, no faults found, they can't duplicate my no start condition. They call and say they found no fault, bike starts the day after the tests cold, without any carb cleaner, they say bike is ready to be picked up.
I leave work a littler early as they are closed the entire Labor Day weekend and when I arrive they go to get bike, and it won't start :confused:
I wander back into shop area as they are attempting to start, bike finally fires up. Mechanic is there then in addition to Service Writer, and says "do you smell that? He smells coolant on start up, a quick check of coolant reservoir shows its at the minimum level. The same shop replaced the coolant under recall just 8000 miles ago.
They now feel that I have the defective head problem and I need new heads, possibly cylinders. They state that even though the bike is out of warranty, that Ducati should cover costs :)
This could take a while, but a new improved top end will be worth it.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top