Thought it was battery.. starting problem..

[Milo_357]

Hey guys,

Got a problem starting the bike.  At first I thought a cell had gone bad with the battery.  Went to start it up, it turned over a couple times.  I let it sit a sec, hit the starter again and "thunk" everything died, just like my car does when I lose a cell in the battery.  But my buddy who got me the battery says it's charging up fine and wonders if it's something else.

I am going to load test it today, but in the mean time, any thoughts? Anything to check?

Thanks,

Dell

[Bob_Roller]

Put a multimeter on the battery and see what the voltage drops to when using the starter .

A good battery should be around 10.5 volts during cranking .

Can you use jumper cables and then use the battery from another vehicle, just to remove the battery from the system for troubleshooting .

Remove the battery cables from the bikes battery when you do this .

[Milo_357]

Can you use jumper cables and then use the battery from another vehicle, just to remove the battery from the system for troubleshooting .

Remove the battery cables from the bikes battery when you do this .

Bob, I'm not sure I'm following you on this part. use jumpers to do what now? Remove the battery, THEN use jumpers to see if it's the battery?

Sorry I'm kind thick today...  

[Bob_Roller]

Remove the cables from the bikes battery, use the jumper cables from another battery and connect them to the cables on your bike .

You're just bypassing your battery, to see if the battery is your problem, or if there is another issue with the starting circuit/system .

[Milo_357]

Interesting.  It was the key switch.

Anyone know where to buy key blanks?

And does anyone know where I can find out what the 5 switches on the back of the key switch are?

Thanks,

Dell Moore

[Bob_Roller]

The key is a common one, if you go to  a locksmith, not a hardware store .

Are you talking about the wires on the backside of the switch ?

With the wiring diagram I have, there are only four wires going to the switch .

There are more terminals on the switch, than are used for North  American production bikes .

There is a feature to European spec bikes, where you can drive with the headlight off, just the small bulb under the main headlight bulb is on .

Here are where the wires go .

Terminal 53 (at least it looks like 53 on the diagram, it's kind of blurred on my copy) on the switch has a green wire with a violet spiral band .

Terminal 15 has  solid green wire .

Terminal 58 has a gray wire .

Terminal 30 has a solid red wire .

If you have a wire that's green with a black spiral band , it doesn't belong on the ignition switch, it's for internal lighting for voltmeter and clock, which were options available for the bike .

[Matt Chapter]

Last time I bought a key blank, I ordered it from a dealer and they shipped it to me.  The nearest dealer was an hour and a half away.  These days I'd just go to the local shop.  Take it to a locksmith to get the blank cut, naturally.  The new key is much fancier than my old one, has a colored bmw logo instead of one just impressed in the plastic.

[montmil]

How did you determine that the ignition switch was failed?

A pre-disassembly digital photo is a great way to confirm "what goes where" even after checking the manual's wiring diagrams. A pencil and notepad is even easier.

Note the small debossed numbers on the switch assembly. They match up with those small numbers on the wiring diagrams and the wire color codes.

[Milo_357]

How did you determine that the ignition switch was failed?

A pre-disassembly digital photo is a great way to confirm "what goes where" even after checking the manual's wiring diagrams. A pencil and notepad is even easier.

Note the small debossed numbers on the switch assembly. They match up with those small numbers on the wiring diagrams and the wire color codes.

 

Monte, I was basically going on a hunch & suggestion.  My mechanic friend thought it MIGHT be the switch due to the fact that when I turn my bike off, the front headlight stays on until I toggle the highbeam switch.

It still does it even with the new ignition switch.

Any ideas on what is causing THAT problem?  If I forget to check the light, spptt, there goes that battery.

And no, I do know that did not cause the original problem.  

[montmil]

Those hi-lo switches can get funky with long-term wear and usage. Little spring, little ball bearing, little groove, little gummy, lot sticky...

When you're feeling adventurous, Milo, disassemble the switch inside a BIG ziplock bag. You'll catch all those bits that frequently jump into a parallel universe. Inspect 'em, clean 'em up, tiny dab of lube (no WD40) and it'll probably straighten up and light right for you.

To paraphrase Clint, "So tell me, Milo. Are ya feelin' lucky?"  

A little new key every now and then is a good thing. 8-)

[Bob_Roller]

What happens to the headlight and instrument internal lighting, when you push the starter button ?

On US, maybe all North American production bikes, not real sure, there is a light control relay that turns off the head light and instrument lights when the starter is engaged .

It gets it's power from the green with violet spiral band wire that goes onto one of the terminals on the ignition switch .

I'm thinking, that if the green/violet wire is removed from the ignition switch, the head light should not work, if it still does, the light relay may be stuck in the closed position.

 But why cycling the head light switch would make light go out, I don't have an answer for that !!!

[Milo_357]

What happens to the headlight and instrument internal lighting, when you push the starter button ?

On US, maybe all North American production bikes, not real sure, there is a light control relay that turns off the head light and instrument lights when the starter is engaged .

It gets it's power from the green with violet spiral band wire that goes onto one of the terminals on the ignition switch .

I'm thinking, that if the green/violet wire is removed from the ignition switch, the head light should not work, if it still does, the light relay may be stuck in the closed position.

 But why cycling the head light switch would make light go out, I don't have an answer for that !!!

Makes total sense to me...

That's just my luck!