Mystery problem with starter switch

Joined
May 16, 2013
Messages
88
Location
Olney, MD
Bike
1993 ST1100
This is a real mystery to me. Hopefully someone else has run into this problem and found the solution. Pressing the start button on the handlebar just makes a click sound, coming from somewhere around the dash - definitely not from the starter relay. It started out with the starter not working intermittently. Then advanced to not at all. It seemed to start when I installed a new set up regular handlebars on the bike. But now I have no idea what caused the problem.

Since there was + voltage into the relay but not out, I first replaced that. Nope. Then I saw the connector at the relay had melted at the red wire connection, so I replaced that and also did the red wire bypass while I was at it. No luck. I had also originally tried jumping across the contacts inside the starter switch but got the same result.

Then most recently out of desperation I thought to jump accross the external soldered wire connections on the switch (blue/white to red/yellow) and bingo, it turned over. So even though that switch is very straightforward and you can take it apart completely, this result to me could only indicate a bad switch (the snap on cover was cracked, so I thought...). So I got a clean used right hand switch assembly on eBay, connected it up and...same problem.

Does the switch assembly need to be grounded or something? I tried that without mounting it but made no difference. This totally makes no sense to me at this point. Hardware/wiring wise there isn't anything left to test. I must be missing something really obvious...or not.

Any ideas?
 
[BIG EDIT HERE (see my next post): I didn’t read the OP’s post closely enough. This quote was what got me started down the interlock rabbit hole:
there was + voltage into the relay but not out

While the info that follows is true, it is apparently not the actual problem. I should have followed my own advice and looked at the wiring diagram. DOH :doh1:

The problem is ‘downstream’ of the relay. ] In order for the circuit to be completed and power sent to the starter by the relay, the starting/ignition safety interlocks must be correct to ‘trip’/trigger the relay, to ground/no wire break or resistance. Have a look at the colored wiring diagram. IOW, the clutch, neutral and side stand must be correct. I.E. - if the clutch lever is pulled, the ST will start even if in gear and the side stand is down. If the ST is in neutral the ST will start even if the side stand is down. If the side stand is down and the clutch is released with the engine running and in gear the engine dies. You get the idea.


There’s also an excellent diagram of the interlock system in the Honda Service Manual, p. 18-2 (I can clip an image if requested), troubleshooting chart p. 18-4.

John
 
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This is a real mystery to me. Hopefully someone else has run into this problem and found the solution. Pressing the start button on the handlebar just makes a click sound, coming from somewhere around the dash - definitely not from the starter relay. It started out with the starter not working intermittently. Then advanced to not at all. It seemed to start when I installed a new set up regular handlebars on the bike. But now I have no idea what caused the problem.

Since there was + voltage into the relay but not out, I first replaced that. Nope. Then I saw the connector at the relay had melted at the red wire connection, so I replaced that and also did the red wire bypass while I was at it. No luck. I had also originally tried jumping across the contacts inside the starter switch but got the same result.

Then most recently out of desperation I thought to jump accross the external soldered wire connections on the switch (blue/white to red/yellow) and bingo, it turned over. So even though that switch is very straightforward and you can take it apart completely, this result to me could only indicate a bad switch (the snap on cover was cracked, so I thought...). So I got a clean used right hand switch assembly on eBay, connected it up and...same problem.

Does the switch assembly need to be grounded or something? I tried that without mounting it but made no difference. This totally makes no sense to me at this point. Hardware/wiring wise there isn't anything left to test. I must be missing something really obvious...or not.

Any ideas?
Hey buddy! It occurred to me that since you got activation after jumping the first switch the second switch might also be bad.
 
I didn’t read the OP’s post closely enough. Sorry. This:
jump accross the … connections on the switch (blue/white to red/yellow) and bingo, it turned over

With the ignition switch on, the headlight is powered on through the blue/white lead through the handlebar switchgear. (BTW, when the starter switch is pressed the power to the headlight is momentarily turned off). Jumping across the headlight’s blue/white lead to the yellow/red lead will send power to the starter relay and if the other side of the relay can reach ground through the starter interlocks the relay will be tripped and the starter will spin. IOW, what you reported is normal… there’s 12V at the blue/white with the ignition on, so jumping to the starter relay’s yellow/red will send power there. If I’m all wet others will weigh in soon….

Again, sorry for any confusion.

Edit: power is sent from the ‘D’ fuse (black) to the lean angle sensor/relay, then to the handlebar switchgear housing (black/yellow), and then when the start switch is pressed power is sent to the starter relay (yellow/red). Your problem would seem to be in this circuit. Try bypassing the lean angle system (aka BAS {Bank Angle Sensor} which was a recall item on early models}), to see if 12V gets to the handlebar switch. The problem may not be the BAS or at the handlebar; maybe inspect the big connector behind the steering stem… wouldn’t be the first time someone found a major corrosion problem in the three big connectors there.

Good luck.

John
 
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Pressing the start button on the handlebar just makes a click sound, coming from somewhere around the dash - definitely not from the starter relay.
That's just the headlight relay getting de-energized (US type starter buttons operate 1x NC (headlight) and 1x NO (starter)
Have you also tried flicking the KILL switch a couple of times? (I'd clean & service those switch-gears once a year...)
 
Thanks so much for all the replies! I only got a notice about the first one. Very helpful. I'm guessing the replacement switch is probably OK (it's very clean and no cracks, unlike my existing one). Should have checked my wiring diagram re: what wires I was jumping - but at least the relay/solenoid/starter seem fine. Will look into all the suggestions and let you know how it goes.

FYI this is a 93 US standard model, very low miles considering (~30k I think).

Hey Tom - just realized one of these was from you! Reading the bikes list and thinking, wait a minute, that sounds REAL familiar!
 
Depending on the year, the kill switch needs to be on for the hot side of the starter switch to be energized.
 
It's a 93. Not sure what are you saying - the kill switch normally is off to start the bike.
 
Please keep us posted, Clay.

Seven years between posts, all in your own two threads. What ever happened to your ‘93 in this 2014 thread?

Regards, John
 
I will this time, promise! I now have a short list of things to try. Thanks for offering to send me the wiring info., but I have the factory manual.

I can't recall what the shop did to fix that battery problem, but it never came back. That is the same 93 ST I have today, and it gave me no problems after that. See attached. I didn't realize there were that many responses - I'm only occasionally getting email alerts, this time as well. I also have 5 other bikes that have required a lot of attention since that battery issue - thankfully my ST has not!

All I've really done since then is, earlier this year, I installed a full Delkevic stainless exhaust ($734 delivered, which I thought very reasonable - had not found anything near that price previously). I'll do a post on that in case anyone is interested. Had a couple of issues with it, but still a very nice system.

Thanks again for your detained help and suggestions, and time John!
 

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Nice looking ‘93, Clay. Always liked that colo(u)r; second beST to Sparkling Silver Metallic, of course. You need to put some miles on that beauty!

The colored wiring diagrams linked above are much easier to use than the black and white one in the Honda Service Manual. I carry a copy in my onboard aux tool kit. IIRC, l the USA 91-94 ST1100s can turn over the starter with the Engine Stop switch on (see the colored diagram), just no power to the coils.

Assume you’re still running the OEM 28amp alternator? Any particular reason you installed the Delkevics? Rotted pipes/collector?

John
 
Yeah, I really love the color. And it's in great shape, no fading or cracks, etc. I got the Delkevics partly because I can never leave my bikes alone (been that way since I was a kid :), but the stock headers were getting a bit rusty and the mufflers are just so heavy. The system looks great (to my eye at least) but is a bit too loud for me, so I put some small baffles between the lead pipe and the mufflers - which helps, although I only got to run it once before the starting problem hit.

Have the original alternator. Nothing added that would require more.

And THANKS for the link to the colored diagrams - very helpful. Printing out now. Should have done that sooner....
 
ave the original alternator. Nothing added that would require more
I would keep an eye on all the connectors involved with the alternator.
First off I would put a blank sheet of paper under the alternator overnight, check in the morning for signs of oil leaking onto the paper.
Inspect the red connector for the three yellow wires coming from the alternator to the voltage regulator. Inspect the white 6 wire connector to the VRR and finally inspect the red connector to the main relay.
It doesn’t take much to overload the system, you’re probably running standard H4 headlights which adds 20 to 30 watts more than the OEM bulbs. A phone charger, GPS just add to it, even heated grips can put you over the capacity of the 28 amp alternator.
 
^^^^^^
I I I I I I. Good advice from The Kiltman (Robert). To eliminate a common source of corrosion/resistance that has contributed to many 28amper failures, I recommend cutting out the red 3P with the three yellow leads from the stator. I’d use uninsulated butt connectors with a quality crimper and polyolefin shrink tubing; others say solder (I don’t). Then zip-tie to the frame. When you do the 40amper upgrade this wiring harness is tossed.

For less than half the cost of the louder mufflers you could have a pretty bulletproof alternator. And more power! After a hard start and then immediately getting stuck in stop-n-go traffic on a hot day causing the radiator fan to run a lot, your alternator can’t recover your battery, it stays overloaded. A switch to cut off the headlights then would be prudent. If you’re not now running a digital voltmeter that registers to tenths of a volt, I highly recommend that you do. They are cheap and can give you early warning of impending failure. You’ll thank me someday.

There’s plenty of info on inspecting, testing, and preventing ST1100 28amp charging systems failures here and on ST-Riders.net

Good luck.

BTW, where is “claytonia”?

Regards, John
 
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He has more bikes than I have had in my 48.5 years of riding. My 1100 is only my fifth bike, all Hondas, and this is actually the first time I've had two at the same time.
Yeah, it's a serious condition for sure! :p:eek:. My Tenere is the only bike I've ever bought new (hard enough to find one new, let alone used - I was lucky!). And it's bike #19 for me - started when I was 13 or so, and I'll be 70 next year. Maybe I'll post some pix - as I mentioned, the ST is definitely one of the most stock bikes I've owned (as is the Tenere) - the urge to tinker and modify is an equally serious, lifelong habit. Although I'm finding it less and less rewarding as my frustration tolerance with mechanical work has increased o_O .....
 
I would keep an eye on all the connectors involved with the alternator.
First off I would put a blank sheet of paper under the alternator overnight, check in the morning for signs of oil leaking onto the paper.
Inspect the red connector for the three yellow wires coming from the alternator to the voltage regulator. Inspect the white 6 wire connector to the VRR and finally inspect the red connector to the main relay.
It doesn’t take much to overload the system, you’re probably running standard H4 headlights which adds 20 to 30 watts more than the OEM bulbs. A phone charger, GPS just add to it, even heated grips can put you over the capacity of the 28 amp alternator.
Thanks for the alternator advice, and I'll check for the oil leakage - once I get it running again!
 
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