Ignition Switch suspect

After turning on the ignition all the warning light can flicker if the key is wobbled about, didn't worry me too much but now have a pretty serious misfire and erratic running both when riding and on tickover, cleaned plugs and have now ordered four new to see if thats the problem, but they looked OK when removed, the bike is 2004 ST 1300A Pan with 28000 miles on clock, been garaged for last few years but started first pop and ran ok on first outing for twenty off miles, could the misfire be due to something going on with the ignition?

Could be ground issue, old fuel in tanks, or possibly ignition switch. Check out tech on grounding issue.

The following is just information which may prove useful down the line. I hope its as simple as a bad earth connection though !!

Since the ignition switch turns on most of the circuits required for running the engine (either directly or via relays), the fact that the lights flicker when the key is wobbled about would suggest that this is the place to look first.

I'm guessing since you are based in Wales, that you have the HISS system ? This is not likely to be a problem. While a fault in the HISS may cause problems starting, once started, the engine continues to run without the chipped keyfob being present. HISS only needs the chip in order to start the engine.

I have absolutely no experience of repairing or replacing faulty ignition keys on the 1300, so I can't help there I'm afraid. But I can surmise from looking at the microfiches (I use Lings Honda for this). There are 3 main parts to the ignition key - the locking barrel into which the key fits. On top of that is the receiver to detect the presence of the HISS chip in the key handle; and underneath is the base unit which performs the electrical switching.

You are unlikely to need the receiver.
If you decide that you need a new switch base unit - the part number is 35101-MCS-G01, and seems to be the same unit for models from 2002 to 2014 in the UK - so getting a second hand one from a breakers yard from a newer model should be no problem.
The switch mechanism is terminated with a 6 pin connector, which must plug into the wiring harness.

If it is the electrical switch in the base unit that is the problem, then your existing ignition keys and chip will still work. If you end up replacing the barrel, then you will need a key that is cut to go with it. It is possible to remove the chip from your old key and put it in the head of a new Honda style key. For testing, the chip doesn't need to be integrated with the key - the bike will start with a valid chip placed alongside the head of a non-chipped key, and the engine will continue to run after the chip is put in your pocket - until the ignition key or the red kill switch is turned off.

Rubberdarts said:

Could be ground issue, old fuel in tanks, or possibly ignition switch. Check out tech on grounding issue.

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++1. Check all of your grounds, the battery and the big plug under the left fairing before digging in further. I doubt it is the ignition switch. Next thought is bad gas.

jmcarruth said:

++1. Check all of your grounds, the battery and the big plug under the left fairing before digging in further. I doubt it is the ignition switch. Next thought is bad gas.

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It was the information that the warning lights flickered when the key was wobbled about that made me try to think of something else. It could well be an earth, it could be the connectors, but I'm not sure that bad gas would do that !

jfheath said:

when the key was wobbled

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+++1. It could be a just bad earth/ground. And that might be my first thought if the switch body itself wobbled. But if it's just wobbling the key it's difficult for me to pin the hopes on something external.

Ground points are fairly easy to inspect and that's free so why not. But a bad switch wouldn't surprise me. Bad gas?? That would.

I had this very same thing happen to me with a Ducati that I had, even to the point of replacing the ignition switch. It turned out to be a bad main ground connection. Wiggling the key provided just enough vibration through the frame to allow the ground to complete its circuit. I cleaned and tightened all grounds and applied dielectric grease, no more ground issues. Your ST has several ground connections from the wiring harness to the frame, and the big one from the battery. Plus, that big plug under the left fairing has been known to have ground issues.

thanks I will check all the grounds out, The bike ran well on the old fuel when I first went out and then I topped up so doubt if the fuel is problem, also the speedo and rev counter etc stopped displaying while motoring and wiggling the key brought things back, it did not misfire while this was happening so maybe I have a couple of faults, will check grounds first

SORTED : new plugs arrived after nI fiddled about under the tank etc, repaced front offside plug, no change, replaced rear nearside spark plug : hey Ho all running like it should. replaced other plugs and she is as Smooth as a pan should be, thanks for suggestions, out and about again and all polished up, north west Scotland here we come !!

Well done for getting it sorted. So the problem was with the spark plugs ? So what was the issue with the warning lights flickering ? Is that sorted as well ?