Wolf - More Electrical Gremlins

[Evil Tharg]

Hi Guys,

I need some more technical advice please.

Having had to replace my EHC with a brand new one (thanks BigDogPartsKing) just 600 miles ago when I'd only had the bike for a week I've been paranoid about the electrics ever since and sure enough today they bugged out again.

The fault was initially the same as last time, cruising at about 65 on the highway when suddenly everything dies, no speedo, no lights, no engine, nothing, so I pull over and turn it off then on again and bingo, this time it's all fine, lights up, fires up first press of the button and I rode it home. Weird or what?

Any clues out there? Was it just a random gremlin or could it be more serious? I was thinking about buying the new KMW EHC replacement kit and installing it anyway but I don't want to throw money away if this could be something else. Also, my brake light works when the ignition is off, is it supposed to do that?

Any advice you can offer will as always be most gratefully received.

 

[BigDogBro1]

You have a connection that is getting loose and cutting power to the EHC or EFI.

Battery condition must be 12.8 volts or better when OFF charger an hour.

Always have the battery on a Battery Tender when not riding.

You need to check all battery connections for clean and tight at battery terminals. Bigger wires go on FIRST towards terminals.

Check all wire crimps for good tight crimp. Or you have a harness connection that is intermittent.

 

[Evil Tharg]

Thanks for the advice Bro,

The battery is all good, it's brand new and permanently on a tender, and so are the terminal connections, all tight with the bigger wires connected first. I guess I need to check the harness next.

One thing that did occur to me was could it be an intermittent fault or a short in the ignition switch?

 

[Evil Tharg]

So after another few weeks of faultless riding the bike died again yesterday evening, exactly the same symptoms as before, it was like someone turned the ignition off and threw away the key, no power to anything. But, same as before, when I pulled over and switched her off and back on again she fired right up and I rode home without any further issues. Any idea what gives?

Just to help here I have checked all the connections and they are all tight, battery voltage is good and the bike is on a tender. I don't figure it's a loose connection because on both occasions I have been riding on smooth surfaces and believe me the roads here are so torn up if it was a loose wire it would be going off every ten seconds.

Anyone have any idea what is going on here?

 

[Brew]

Do you have anything heavy hanging off the ignition key ring?

 

[KaptinAmerika]

Just another example of why the EHC shouldn't be considered the first culprit with these issues.
I just finished doing major harness repairs to a customer's bike. Same issue, intermittent dying while riding. EHC had been replaced but eventually failed again. After a number of hours of rework I found two hidden mild shorts which were on circuits tied to the B Buss voltage. The shorts were causing the step down conditioner to go buggy and eventually fail.
Under the coil cover is a JST connector for your ignition switch. Disconnect it and jumper the female side to turn the bike on, don't worry its just a low voltage ground signal to the EHC, ride the bike that way. If the bike does not die you have a defective ignition switch. If the bike does fail then a thorough review of the bikes entire wiring system is due in order to find the culprit causing the failure.

 

[BadDawg Bill]

Just another example of why the EHC shouldn't be considered the first culprit with these issues.
I just finished doing major harness repairs to a customer's bike. Same issue, intermittent dying while riding. EHC had been replaced but eventually failed again. After a number of hours of rework I found two hidden mild shorts which were on circuits tied to the B Buss voltage. The shorts were causing the step down conditioner to go buggy and eventually fail.
Under the coil cover is a JST connector for your ignition switch. Disconnect it and jumper the female side to turn the bike on, don't worry its just a low voltage ground signal to the EHC, ride the bike that way. If the bike dies you have a defective ignition switch. If the bike does not fail then a thorough review of the bikes entire wiring system is due in order to find the culprit causing the failure.

This sounds right to me too. You have something losing contact and the first place I'd look at is the ign switch. Good luck.

 

[DRBarnhart]

Just another example of why the EHC shouldn't be considered the first culprit with these issues.

Ain't that the truth!!!

Under the coil cover is a JST connector for your ignition switch. Disconnect it and jumper the female side to turn the bike on,... ride the bike that way. If the bike dies you have a defective ignition switch. If the bike does not fail then a thorough review of the bikes entire wiring system is due in order to find the culprit causing the failure.

I think you mean to say, "If the bike does NOT fail you have a defective ignition switch. If the bike DOES die then a thorough review of the bikes entire wiring system..." is in your future. True?

Dennis

 

[KaptinAmerika]

Yep, I'm working too many hours for sure.

 

[Evil Tharg]

Thank you so, so much for your advice guys, especially you KA, I will follow it up and let you know the results. It is so helpful to me having this forum, being so far away I really don't know what I'd do without it.

Just to advise you all though I did have a Big Dog rubber key-ring hanging off the key but after the first failure I took it off because I thought there was an outside chance it was a factor, it wasn't. I have also wiggled the key very vigorously with the engine running but have been unable to duplicate the fault by doing so and it doesn't seem to be triggered by bumps in the road either.

It does seem highly unlikely to me though that the EHC has failed again so quickly, I have only done 700 miles since replacing it but the original one was definitely fried and the symptoms of the failure were quite different, when the first one went the speedo froze at the speed I was travelling at, now it drops to zero.

 

[Evil Tharg]

Electrical Problem Solved - Ish

Hi Guys,

Due once again to the excellent advice from this forum, especially from KA, I opted not to just blame the EHC as had been my first assumption and dig a little deeper and to my great surprise I found the problem. I should point out here that I am really no mechanic much less a wiring guru but by the simple expedient of removing the switch mounting and fiddling around with the wires I found the fault, so what do I do about it?

Behind the switch there is a short cable that terminates in a sealed male connector, this is plugged into a female connector which is I assume part of the harness and leads to the EHC. There appears to be an intermittent short or break in the short cable just before it goes into the connector, I can cause the bike to shut off by wiggling this cable so can I just cut the connector out and hard wire the two cables together? I assume the connector is there so it would be easier to swap the switch out if it fails? Or does it serve some other purpose as well? I can't think what.

All advice gratefully received as always. Thanks Guys.

 

[Evil Tharg]

Oh I forgot to add that the reason why I assumed it was the EHC, well apart from the reputation that unit has for being unreliable, was because I thought that if it was a short or an intermittent wire connection it would be more likely to happen if I hit a bump, but it never did. Weird.

 

[ksmike]

David,

Your post got me thinking about my past "unexplained" powering down situations. The whole bike powering down is a dangerous deal. I have had it happen in heavy traffic at 70 mph...not good... and at night in pitch dark (kills headlight) really not good...

I had a rubber key fob on my key for a while, but that seemed to make the problem worse. Now I just run a bare key.

Anyway I played with my key a little while ago and found out that if you momentary go from the on position to off and back to on again it may kill all the power to the bike. But it is somewhat random when it does this. Its interesting that the key can actually be on and the bike is not powered up.....but putting the key back to off for a second then to on will power the bike up

An intermittent key switch or key switch wiring could really cause some dangerous situations.... (just ask GM)

 

[KaptinAmerika]

I would just replace the JST connector for consistency in the wiring but you can just remove the connector and hard wire it.

 

[rottie1]

I had to replace my key switch due to the same problem bike would just randomly cut out I wired in a togle switch and ran it like that with no problems for almost 2 years