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newbie1 31 Aug 2015 16:40

Before looking at the fuses, and I decided to test the ignition switch to see what I could find.

I disconnected it from the wiring harness and started testing with a multi-meter. Then, after re-connecting the switch and turning on the ignition, BOOM ... I've got lights, telltales, everything ... and the bike is once again turning over.:clap:

Any ideas why?

Now I'm going to once again test at the coils to resume troubleshooting why I'm getting no spark at the plugs.

Thanks Warin.

Warin 1 Sep 2015 00:16

Quote:

Originally Posted by newbie1 (Post 514729)
Any ideas why?

This kind of fault is called an 'intermittent' .. it will come back .. then disappear .. only to reappear. Of course it will reappear at most inconvenient times.

It could be a loose connection .. the earth lug for the wiring harness not being tight for instance. It could be lot of things.

Quote:

Originally Posted by newbie1 (Post 514729)
Now I'm going to once again test at the coils to resume troubleshooting why I'm getting no spark at the plugs.

Ok. I think I have posted what to do about that above.

Warin 1 Sep 2015 04:47

When an intermittent occurs your best off trying to isolate where the fault is.

If you test something and find it OK .. you still don't know if the fault is within the thing you tested, particularity if the fault disappears after the test as the fault may have disappeared just before you started the test.

What I think should be done is trying to find where the voltage disappears with minimal disturbance to things. By testing at the fuses you find out if the voltage is getting to the fuses, getting past the ignition key switch and getting past the headlight switch. That is 3 things for one group of tests in one location, minimum work and disturbance for a fair amount of information.

-------------------------------
Same for the ignition system.

Check for sparks as you flick the engine kill switch on and off (the warning lights should come on and off .. if they don't you have a problem that does not involve the ignition system itself but the supply to the ignition system.

If no sparks and warning lights working above then

Check that the central pin short/open of the HES connector causes spark (as detailed in another post). If you get sparks here it would suggest the HES is faulty. No sparks suggest the ICU/coil or supply problem.

TheTraveler 1 Sep 2015 06:12

Glad to hear you got it going. Hope you isolate the problem and get it permanently fixed. Best of luck.

newbie1 1 Sep 2015 16:15

Today, Tuesday, I have a full day devoted to other tasks which have been neglected since I've been at this. I will be back at this Wednesday morning.

Thanks Warin.

newbie1 2 Sep 2015 20:53

I tested the fuses. You said "one fuse will have battery voltage at any time, two with the ignition key switch on the remainder with the ignition key switch on and the headlight switch on." You were right in that one did have voltage at any time, all 4 with both the ignition and headlight switches on, but only one fuse had voltage with just the ignition on, which was the same one that has voltage all the time.

I also troubleshooted the coil like you said. I disconnected the black lead to the primary coil, laid the base of both spark plugs on the cylinder heads with the HT leads connected, then jumpered the disconnected primary-coil terminal intermittently to ground with the ignition on and kill switch off, and got no spark at the plugs.

I also did as you said and jumpered the middle receptacle of the beancan-plug connector to earth intermittently with the ignition on and kill switch off, no spark.

Anyway, I will confess right here what else I did. Frustrated to no end, I bought a used beancan and a used ICU and installed them. Remember that I also have a new coil too. Add to that new HT leads, new plugs and new fuses.

All lights work, the engine turns, but I STILL CAN'T GET THE BIKE STARTED!

What the hell, Warren. What else can I do?

Warin 3 Sep 2015 00:30

?
If the kill switch is off ... you won't get spark.

For testing (and running) you have to have
the ignition key switch ON
AND
the engine kill switch ON

Take a break and relax ... I think your stressing out .. I do that too. :(
----------------------
Just because something is "new" that does not mean it works.

----------------------------
Ok fuse voltage readings indicate the key switch is working.

Do you have battery voltage at the coil? - the smaller leads not the large HT leads that go to the spark plugs. That would confirm the the switches are ok and that the leads to this point are ok.

Then test the coil by shorting the negative terminal - the one with the two small black wires going to it.
No spark means fault in the coil or the HT leads or the spark plug caps or the spark plug.

newbie1 3 Sep 2015 00:48

1 Attachment(s)
Warren,

when I said the kill switch is on, I meant that it is set to one of the two positions that make starting the bike impossible.

When I said it's off, I meant that it's in the middle position, where it needs to be to start the engine. I apologize, again, for another instance of this flustered newbie not speaking correctly, though I believe I did do this test correctly.

Do you have battery voltage at the coil?

Yes.


Then test the coil by shorting the negative terminal - the one with the two small black wires going to it.

I did that twice.


No spark means fault in the coil or the HT leads or the spark plug caps or the spark plug.

Like I said, all of these things are brand new. Maybe I fu..ed up the new coil somehow. I'll throw the old one back in tomorrow and see if that changes anything. It won't, though. The resistances of the two units are identical.

And I've already tried two sets of plugs -- the ones that were in the bike when it went down and then two new ones.

You said that just because something is new doesn't mean it works. So, how do I test the HT leads? The caps?

And please disregard the attached picture. I answered my own question about it.

Thank you.

Warin 3 Sep 2015 05:08

Test the HT leads ..

you can test for continuity

From the coil connections to the spark plug connections .. should be about 5,000 (or 5k) ohms. That is 5000 for each lead + cap , disconnected from anything else. They can be more if someone has used resistive lead - that could add another 5000. As long as it is less than say 15,000 and more than 4,300 ohms each that would be ok.

How old are they? If more than 10 years I'd replace them.
You cannot test for insulation .. well not with your normal DMM. This is the resistance from the inside to the outside and must be OK at a very large voltage .. say 20,000 volts .. your DMM only has around 9 volts. Testing at 9 volts will not reveal what happens at 20,000!
I prefer the solid copper leads rather than the resistive ones myself. Then I use NGK 5k resistive caps.

======================== Logic?

Yes, we have no bananas ... means? Are you French = no bananas, English = yes we have bananas.
Nay? Dutch = No. Greek = Yes.

newbie1 3 Sep 2015 17:25

Warren,

your help here should prove to be invaluable.

I tested my new leads as you described. I got 1K ohms.

I bought the wrong leads.:clap:

When I bought them, I merely asked a man at Euro MotoElectrics if they fit the new coil I was also buying from him. He asked me for the make and model of my bike, I told him, and after some hemming-and-hawing he said they would work.

They don't.

My fault, though. My temper is the bane of my existence, and if I didn't get as flustered as I do at times like these it would have dawned on me to get the part# I needed and verify it was the same as the leads I bought.

So I am over-nighting the correct leads. Tomorrow, Friday, I will install them. Whether or not the bike starts afterward, you'll be the second person to know.

Sincerely,

Shithead:stupid:

newbie1 4 Sep 2015 17:33

Got the new leads.

Both tested at 5K ohms.

Put 'em in.

Guess what?

NOT A FU..ING THING!!!!!!!!!!!!!!!!!!!!

Driving it to the mechanic today. 250 mile round trip, and I ain't looking forward to it.

God hates us all.

newbie1 5 Sep 2015 16:47

The problem is solved.

A bad diode in the wiring harness.

Thanks again for all of your help, Warren. I really appreciate it.

Until next time ...


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