Electrical Power Delay ??

03-04-2015, 02:45 PM

Hi
Turn the key (nothing happens) .....10sec....20sec later the instrument panel lights up.....
She then works perfectly, starts and runs etc.

Switch off and attempt a restart, same delay occurs. no electric for a period of time.

1997 m750 10,000 miles. All original. full charge. serviced by ducati fir the last 6 yrs
Budget nil
technical ability nil... i do have a haynes to refer to though

help or advise appreciated

dave

Dukedesmo · 03-04-2015, 03:39 PM

Check the main (yellow) relay under the seat, feel if it 'clicks' at the time the power comes on.

utopia · 03-04-2015, 03:50 PM

Have a listen to it too.
You should just about be able to hear it click.

The cover prises off easily enough if you want to check that the contacts are clean.

03-04-2015, 04:34 PM

Yes, clicks when the key is turned.... Then wait for it to decide when to come to life

Nickj · 03-04-2015, 05:24 PM

Carbies haven't got anything to delay power up other than the relay, it might be that it is just making a poor connection on one of the contacts or it is worn out...
I'd go with Utopia on this, get the top off look at the little contact pads to see they are clean and shining, you can give them a clean with contact cleaner or use very fine wet and dry pulled through a pair just to resurface.
If it just moves really slowly, need the top off to see this, when the bikes powered up then you need another.

03-04-2015, 06:15 PM

The relay being the yellow thing?
So it's click doesn't mean that it's necessarily working?
It's not got the cleanest connection in the world, but does click immediately. I'll give it and the connections a good clean.

Darren69 · 03-04-2015, 06:26 PM

I would check the connections going into the relay too. Clean the pins.

utopia · 03-04-2015, 07:20 PM

Yep, the yellow one.
There is also a black, indicator relay there, and probably a relay for the sidestand cutout switch too.
The yellow one is a so-called "general relay" and, although mine has been fine for 14yrs so far, many people report problems with them and some advocate carrying a spare.
Upshot is that its worth replacing anyway if its a bit iffy, but a temporary clean-up might at least confirm the problem and get you mobile in the short term.
The click is the mechanical noise from the relay as it closes the contacts but that doesn't necessarily mean that electrical contact is achieved immediately if the contacts are dirty or corroded.

Electrics isn't my best subject but bypassing the relay might be an acceptable test, though its there for a reason so there must be a downside to this test somewhere, I guess.
I'm sure others will be able to advise.

03-04-2015, 08:38 PM

after spend all day googling. I think it can only be this at fault.
I'll try and source a new one

Dukedesmo · 03-04-2015, 09:26 PM

The main (Yellow) relay on my 916 developed a similar problem: There are 2 switched contacts (both 'Normally Open') that close when activated but over time they can arc and corrode. Sometimes mine would not make contact or would do so after a couple of seconds.

I cleaned the contacts to get it working again but then replaced it anyway as it would likely start playing up again soon, and at £6 or £7 I reckon I could stretch to a new one after 14 years...

I also keep a spare in the workshop.

Flip · 03-04-2015, 11:31 PM

Yep I agree with everyone on this- it is almost certainly a poor connection.

Mine went intermittent about ten years ago and the bike would simply die then pick up again when contact was made. Not good for your confidence while out riding.

When I looked into it I found that on switching the motor off via the key resulted in the relay arcing as the contacts opened causing them to pit over time-which I presume means some residual voltage is coming from the coils.

Oddly when the motor is turned off with the 'kill switch' it doesn't arc.

utopia · 04-04-2015, 02:01 AM

Well now, I wonder whether that's why mine has lasted so long then ?
I almost always kill the motor via the kill switch rather than by the ign key.
Then again, is it really all that odd ?
I haven't studied the wiring diagram and my electrics skills are not brilliant, but would it be correct to say that the general relay carries less load when the motor has previously been killed at the kill-switch, and therefore the potential to arc is much less. And conversely, when the key is used to switch everything off at the same time, the gen. relay has a much larger load to deal with and is therefore more likely to arc ??
Anyway, I think its probably about time I changed mine now, or at least had a spare on the shelf.

04-04-2015, 11:38 AM

Well, I've removed the yellow cover. Blown on it... And now it works

03-04-2015, 02:45 PM	#1
davkyt Guest Posts: n/a	Electrical Power Delay ?? Hi Turn the key (nothing happens) .....10sec....20sec later the instrument panel lights up..... She then works perfectly, starts and runs etc. Switch off and attempt a restart, same delay occurs. no electric for a period of time. 1997 m750 10,000 miles. All original. full charge. serviced by ducati fir the last 6 yrs Budget nil technical ability nil... i do have a haynes to refer to though help or advise appreciated dave

03-04-2015, 03:39 PM	#2
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,901	Check the main (yellow) relay under the seat, feel if it 'clicks' at the time the power comes on. __________________ M900, 916, LeMans II.

03-04-2015, 05:24 PM	#5
Nickj Too much time on my hands member Join Date: Jun 2007 Location: Forest Of Dean Bike: S2r Posts: 3,208	Carbies haven't got anything to delay power up other than the relay, it might be that it is just making a poor connection on one of the contacts or it is worn out... I'd go with Utopia on this, get the top off look at the little contact pads to see they are clean and shining, you can give them a clean with contact cleaner or use very fine wet and dry pulled through a pair just to resurface. If it just moves really slowly, need the top off to see this, when the bikes powered up then you need another. __________________ "The final measure of any rider's skill is the inverse ratio of his preferred Traveling Speed to the number of bad scars on his body." Song of the sausage creature

03-04-2015, 06:26 PM	#7
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,095	I would check the connections going into the relay too. Clean the pins. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

03-04-2015, 09:26 PM	#10
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,901	The main (Yellow) relay on my 916 developed a similar problem: There are 2 switched contacts (both 'Normally Open') that close when activated but over time they can arc and corrode. Sometimes mine would not make contact or would do so after a couple of seconds. I cleaned the contacts to get it working again but then replaced it anyway as it would likely start playing up again soon, and at £6 or £7 I reckon I could stretch to a new one after 14 years... I also keep a spare in the workshop. __________________ M900, 916, LeMans II.

03-04-2015, 03:50 PM	#3
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,561	Have a listen to it too. You should just about be able to hear it click. The cover prises off easily enough if you want to check that the contacts are clean.

03-04-2015, 04:34 PM	#4
davkyt Guest Posts: n/a	Yes, clicks when the key is turned.... Then wait for it to decide when to come to life

03-04-2015, 06:15 PM	#6
davkyt Guest Posts: n/a	The relay being the yellow thing? So it's click doesn't mean that it's necessarily working? It's not got the cleanest connection in the world, but does click immediately. I'll give it and the connections a good clean.

03-04-2015, 07:20 PM	#8
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,561	Yep, the yellow one. There is also a black, indicator relay there, and probably a relay for the sidestand cutout switch too. The yellow one is a so-called "general relay" and, although mine has been fine for 14yrs so far, many people report problems with them and some advocate carrying a spare. Upshot is that its worth replacing anyway if its a bit iffy, but a temporary clean-up might at least confirm the problem and get you mobile in the short term. The click is the mechanical noise from the relay as it closes the contacts but that doesn't necessarily mean that electrical contact is achieved immediately if the contacts are dirty or corroded. Electrics isn't my best subject but bypassing the relay might be an acceptable test, though its there for a reason so there must be a downside to this test somewhere, I guess. I'm sure others will be able to advise.

03-04-2015, 08:38 PM	#9
davkyt Guest Posts: n/a	after spend all day googling. I think it can only be this at fault. I'll try and source a new one

03-04-2015, 11:31 PM	#11
Flip Registered User Join Date: Mar 2010 Location: Beachtown Bike: M900 Posts: 2,188	Yep I agree with everyone on this- it is almost certainly a poor connection. Mine went intermittent about ten years ago and the bike would simply die then pick up again when contact was made. Not good for your confidence while out riding. When I looked into it I found that on switching the motor off via the key resulted in the relay arcing as the contacts opened causing them to pit over time-which I presume means some residual voltage is coming from the coils. Oddly when the motor is turned off with the 'kill switch' it doesn't arc. __________________ You're perfect, yes, it's true- But without me you're only you!

04-04-2015, 02:01 AM	#12
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,561	Well now, I wonder whether that's why mine has lasted so long then ? I almost always kill the motor via the kill switch rather than by the ign key. Then again, is it really all that odd ? I haven't studied the wiring diagram and my electrics skills are not brilliant, but would it be correct to say that the general relay carries less load when the motor has previously been killed at the kill-switch, and therefore the potential to arc is much less. And conversely, when the key is used to switch everything off at the same time, the gen. relay has a much larger load to deal with and is therefore more likely to arc ?? Anyway, I think its probably about time I changed mine now, or at least had a spare on the shelf.

04-04-2015, 11:38 AM	#13
davkyt Guest Posts: n/a	Well, I've removed the yellow cover. Blown on it... And now it works