engine won't start ignition/ecu cuts starter off

Hi All, Been having electrical problems with My 2008 Bonneville America ! Doing the usual fault finding and parts replacements and searching the Interwebs I have found the following.

It is a fault Common to many Models & and All years of Manufacture ! The starter relay between the ECU and the Bike's starter motor. FAILS ! This is because it isn't weather/water/dust tight if water or dust get into the points/coil inside the relay it is just a matter of time before faulty/failure to crank and hence start ! The symptoms are .... Bike arms( fuel pump etc start ) when ignition is turned on. But when starter button is engaged the starter motor starts to engage ( clunk or stirring noise ) but doesn't continue as ECU cuts starter relay hence all switches off ! This can be flat or dead battery. but once you have eliminated these and fuses etc. The relay should be considered sooner rather than later , I have Googled the hell out of this and many instance found for many machines by model year etc, some have had failure within a few months of purchase ! Mine took 8 yes and 100,000+ klms. The relay shorts internally causing ECU to detect massive Voltage drop ! ECU won't allow starting if Voltages are below optimum 12.1v or so , to protect itself and other sensitive parts from failure.
I have spent several hours pulling plugs apart cleaning, replaced battery and starter solenoid for no reason ! So check relays as soon as battery is eliminated, easiest way. Bridge solenoid externally. If it cranks over at a good speed , it's the relay/ECU issue for sure.

Cheers Mick

 

On several forums I found out how others got round this fault ,
Temporary fix number 1: pull apart starter solenoid , carefully , it is just a sleeve . drill a small hole in bottom of outer cover and put a plastic plunger through it, this enables you to manually push plunger and activate solenoid and start bike.
Temporary fix number 2: run power direct from battery through a momentary switch and direct to signal wire/post on solenoid, does the same as number 1 but electrically, cranking can be done via bothe methods without the ignition being on ! So ensure you want to start your bike and ignition and engine kill switches in the right position, or , you will flatten your battery !!!

I have used method 2. Still have starting issues, but I strongly suspect battery needs a good charge... So time will tell, now just need to find a replacement relay.OOh and work out which and where it's actually located on my bike. lol I know what's wrong just not where it's physically located. I hate lifting/pulling the tank off. It is such a pain, I don't have small enough fingers....

 

Hi all, another update on this infernal problem! Battery charge is fine ! How do I know this, well today I wound the motor over for like five or six seconds continuous, during this time the ecu cut out and came back on twice Third time and bike started up and ran fine ????

There must be an issue with the relay under the tank ! Will pull it out Friday or Saturday, need bike for the WA Xmas run to Wongan Hill's hotel Saturday night dinner...

Cheers Mick

 

Hi Eric, I don't think it makes a difference what system our bike's run on. They both have ECU's with relay between ignition/starter button and if relay is faulty or wiring to and from the relay has broken wire's, the ECU turn's everything off when starting is initiated !! With my new Lithium battery I just keep trying until it Start's. So far it has started within about 8 tries Maximum. Lucky for me there's about 30 or 40 starts in the battery !!! So I have some time and Lee way to find the problems, I think I will probably have to run new wire's just like you did And do New Relay. As I am a school bus driver and our school's break up for X'mas break in two weeks (6 week's) I will take some time and do a lot of check's and cross checking, bike is due for some servicing any way, fork oils wheel bearings and seal's tidy up wiring. LoL.

Cheers Mick

 

Hi all,
Well school holidays are over ! And I found the following faults.
1- Neutral switch - badly worn,loose, leaking and faulty (gave variable ohms reading's in multiple position's)
2- relay had dirt in it !
3- clutch switch dirty !

Hence it took hours to find all 3 where possibly interacting at various times, suppose it had to happen on a 103,000 KLM machine that operates in mainly hot dry conditions !
Action to remedy so far clean out 2 & 3, and pulled out neutral switch, clean it, file back copper washer, refit and slightly tighter than the recommended torque ! Get a new one when this fix starts to muck up again, I put plumbers sealing tape on threads. Seams to be good now ! Many starts and no issues.
Hands now removed from the clasped in prayer position, was a really frustrating process, as three faults all arising @ almost simultaneously !!!!!

Cheers capt.

 

Hi TEZ 217,
Yeah all good now ! I skipped the the hair pulling phase , mainly because I started shaving my noggin @ 38 when I retired from the Army, it has saved me many hrs of effort & wasted time, but this nearly broke my will to resist starting pulling hair again !!! LoL.
Thank god for school holidays Eh ! Well I got some home improvement done too, stripped back Jarah wood floor's in two rooms, sanded and varnished and fixed the bike !!

Cheers capt.