Relay problems?

[nik_the_brief]

Hi all,

Having spent all bloody day rewiring the various cables for the rear light cluster, indicators etc. as they had rotted through and were shorting out. I put it all back together thinking it would be a simple job just to switch on the ignition, check that all was connected correctly and tidy everything away - how wrong I was.

Now when I switch on the ignition I get a horrible buzzing sound from the general relay box next to the fusebox. I checked the wires for obvious shorts but could see nowt. There's clearly a charge going to the relay which makes it buzz. It's like the relay is rapidly opening and closing for a few seconds then it stops doing this and nothing works at all.

I checked Haynes Book of Lies (TM Spacemonkey) which advised me to check the relay by putting 12V through terminals 85 and 86 and an ohmeter across 30 and 27 to confirm continuity - which there was so it seems that the relay is working okay.

Has anybody got any idea at all what might be wrong with the thing, it all seemed fine til I started messing around with the wires but I can see it being that as all seems relatively secure and wires are all going to the right places? I'm at my wit's end (not that I had far to go) :Furious:

[analogue_rogue]

you have an idicator earthing out somewhere.. check front indicator connectors havent earthed on fork or frame.

whats happened is there is not enough resistance on the circuit due to the power not running the full way through a bulb somewhere. this allows the relay to run at super fast speed which is the buzzing you can hear.

if it makes you feel better i had the same problem when i rewired the rear of mine and i had knocked the wiring and a front indicator had earthed on the fork....

[nik_the_brief]

Cheers,

Just to confirm, this would affect the main general relay - not the indicator relay?

Pardon my general ignorance, my talents lie in other areas (I just have to find out what they are!).

[Pomp1]

Main relay are prone to go,your one may be on the way out. Ducati only part I'm afraid

[analogue_rogue]

the indicators would only affect the indicator relay as they are not on the main relay cicuit. best way to test a relay is to tap it and see if it clicks or ticks.. a good relay wont and a dodgy one will.... ( got taught that by an old old old grey haired banjo slinging mechanic)

[Gamsa]

It seems too much of a coincidence that the relay should go when you rewire the bike. The wiring's the main suspect I'm afraid, particularly if the relay test is fine =( Try disconnecting all the unnecessary connections to the indicators, lights and see if it still buzzes when you turn on the ignition, would be my advice

[nik_the_brief]

It seems too much of a coincidence that the relay should go when you rewire the bike. The wiring's the main suspect I'm afraid, particularly if the relay test is fine =( Try disconnecting all the unnecessary connections to the indicators, lights and see if it still buzzes when you turn on the ignition, would be my advice

Thanks for that - I've already tried that by disconnecting the entire rear wiring loom by disconnecting it under the seat. The relay seems to be rapidly opening and closing regardless of the fact that this is disconnected so I think I can discount the rear wiring.

Any idea where I might best start looking for a fault? Could it be something to do with the ignition circuit?

Don't suppose anyone has a spare old relay knocking around that I could borrow to see if it's that by any chance? If not I suppose I could replace it anyway so at least I can discount that altogether.

[Gamsa]

So what else did you do to the loom? Did you touch any of the ignition circuit?

[analogue_rogue]

disconnect the relay and check the power coming in from the relevent wires and makes sure its not back feeding power somewhere.

[nik_the_brief]

So what else did you do to the loom? Did you touch any of the ignition circuit?

As far as I know I didn't do anything else to the loom, just replaced the rotten wires and connections with good ones and tidied it all up. When I put it all back together I was expecting it to work perfectly but then the relay problem kicked off!

I did have ignition problems as it wouldn't turn over only a week or so ago. I replaced the starter solenoid but it made no difference. Took the starter/kill switch apart and made sure it was all working properly (it was). Eventually traced the problem back to a broken wire just underneath the push fit connector by the headstock (leading from the starter/kill switch to the ignition system), replaced that, put everything together and all seemed okay, starter turned over when starter button pressed, everything apparently grand. It was then that I started on the arse end wiring.

Apart from messing round with the wiring at the back the only other thing I've done is to turn the bike round in the garage and put it up on the paddock stand again so I had better light. I suppose it may be that the wiring in the loom near the headstock could possibly be shorting out, I'll make that my next thing to check coz this has me flummoxed at the moment! :thumbsdown:

[nik_the_brief]

disconnect the relay and check the power coming in from the relevent wires and makes sure its not back feeding power somewhere.

That's what I was hoping to do but not sure what power is supposed to be going where (ie. does it short back to negative, if so, which wires to where?) - I was told to check for power at the blue/orange cable, couldn't find any but this was when I tried to connect to the negative terminal and I wasn't sure if this was correct.

Hmm I suppose I ought to be checking my Haynes BOL (TM SM) again.

[Gamsa]

As far as I know I didn't do anything else to the loom

OK, this is seriously strange, then, but should be fairly straightforward to diagnose. The main relay has 5 connections. One is permanently earthed and another runs to the ignition switch which is the coil circuit in the relay. You could check the first with a continuity tester to the battery negative terminal. The ignition switch takes a permanent 12V feed straight from the +ve terminal of the battery (through a fuse). When the ignition is on, the 12V feed from the fusebox is fed to the rest of the fuses. So in other words, the other three connections on the relay are: 2xpermanent +12V which are connected inside the relay and could be tested with a continuity tester, and one wire running to the fusebox (brown).

So, your problem could be a loose connection between the permanent +12V feeds connected inside the relay (red and red with yellow dash in original wiring). It wouldn't hurt to join these outside the relay. You could solder the two together or wire in a cross-piece between them.

Or, you could have a bad connection in the fuse box. Could be fixed by taking out all fuses, removing any corrosion and pushing them back.

Otherwise, ignition switch bad contact between 3&6 (red and green with black dash) when the key is turned to on - you could check this with a continuity tester.

Or a bust relay. Good luck!

[analogue_rogue]

have you got a wiring digram for your bike?

[nik_the_brief]

OK, this is seriously strange, then, but should be fairly straightforward to diagnose. The main relay has 5 connections. One is permanently earthed and another runs to the ignition switch which is the coil circuit in the relay. You could check the first with a continuity tester to the battery negative terminal. The ignition switch takes a permanent 12V feed straight from the +ve terminal of the battery (through a fuse). When the ignition is on, the 12V feed from the fusebox is fed to the rest of the fuses. So in other words, the other three connections on the relay are: 2xpermanent +12V which are connected inside the relay and could be tested with a continuity tester, and one wire running to the fusebox (brown).

So, your problem could be a loose connection between the permanent +12V feeds connected inside the relay (red and red with yellow dash in original wiring). It wouldn't hurt to join these outside the relay. You could solder the two together or wire in a cross-piece between them.

Or, you could have a bad connection in the fuse box. Could be fixed by taking out all fuses, removing any corrosion and pushing them back.

Otherwise, ignition switch bad contact between 3&6 (red and green with black dash) when the key is turned to on - you could check this with a continuity tester.

Or a bust relay. Good luck!

You Sir are a gentleman and a scholar, I shall be following your advice pdq.

Just to be on the safe side (and as they're only £7.61 each) I've ordered a new relay - only downside is that it's August and, of course, Ducati are on holiday this month and my local dealer hasn't got one in stock. I've had this trouble before with a set of pick up coils a few years ago.

[nik_the_brief]

have you got a wiring digram for your bike?

Yep, somewhere in my Haynes manual - all I have to do is to find my reading glasses and I'm laughing! :D

[He11cat]

No use but I have had 3 incidences of relays doing that... one I had to have some rewiring done and had to have a new relay bike conked out just the relay clicked away...main relay.

The next time it was a bad earth I think .. again a find and fix job by my friend a sparky.
The next one was making the sound you described and it turned out was my indicator relay ..(use a torch woman next time)..not the main relay as I thought.
Was a corroded indicator connection replaced the indicators and it worked fine again. that was buzzing and clicking.

If in doubt replace... ring round lots of dealers?? someone must have one!!
Have you tried fleabay ? stupid question I know.
I really should order spares for the sake of it.. it was no joke when it went at a petrol garage in surrey when you live in Suffolk.

[Gamsa]

A pleasure - let me know how you get on and if anything's not clear

it's August and, of course, Ducati are on holiday

If you're desperate to ride, there's nothing to stop you hotwiring the bike by temporarily joining the brown fuse box wire to the +12V battery terminal. Then, all your ignition switch does it operate the lights. You are relying on your steering lock to prevent someone riding your bike away, though, and I'm sure your insurance company wouldn't be amused.

[nik_the_brief]

No use but I have had 3 incidences of relays doing that... one I had to have some rewiring done and had to have a new relay bike conked out just the relay clicked away...main relay.

The next time it was a bad earth I think .. again a find and fix job by my friend a sparky.
The next one was making the sound you described and it turned out was my indicator relay ..(use a torch woman next time)..not the main relay as I thought.
Was a corroded indicator connection replaced the indicators and it worked fine again. that was buzzing and clicking.

If in doubt replace... ring round lots of dealers?? someone must have one!!
Have you tried fleabay ? stupid question I know.
I really should order spares for the sake of it.. it was no joke when it went at a petrol garage in surrey when you live in Suffolk.

Cheers m'dear, despite what you say that was useful (all info is). I'm sure it's the main relay buzzing though as i can feel it when I touch it and it stops when I disconnect the bugger!

I have a set of relays (both the main 'un and an indicator one) in my eBay watch list but I have to wait a whole 8 days for the auction to come to an end - still if they're reasonable they'll make handy spares.

[nik_the_brief]

A pleasure - let me know how you get on and if anything's not clear



If you're desperate to ride, there's nothing to stop you hotwiring the bike by temporarily joining the brown fuse box wire to the +12V battery terminal. Then, all your ignition switch does it operate the lights. You are relying on your steering lock to prevent someone riding your bike away, though, and I'm sure your insurance company wouldn't be amused.

I had thought of that - for several seconds - then discounted the idea as I've managed for a few months without it now (after a bit of a tumble and knackered collar bone at easter) so another couple of weeks will be liveable!

I'll use the time to get her sorted properly then I won't have to worry. To be honest she's in bits and really should be completely stripped down and tarted up from scratch but she is my main transport when the bird is at work and needs the family car!

[Gamsa]

Amazing how simple it is to do, though, isn't it? My seat doesn't even have a lock.

[analogue_rogue]

Amazing how simple it is to do, though, isn't it? My seat doesn't even have a lock.

how does it stay on? when your not sat on it obviously!

[Gamsa]

Oh, I put a bracket from an ST4 on and swapped the key mechanism for a pull cord which lives by the brake light. I preferred the shape of the DP ST4 seat. You just pull a wire with a bullet connector crimped on to lift the seat!