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New battery, still no spark. Starts on battery charger

14K views 99 replies 10 participants last post by  whoaru99 
#1 ·
I got a project Nomad a while back, got it going and then ordered up some parts.
https://www.vulcanforums.com/forums/15-vulcan-1600/304426-2006-nomad-no-fuel-no-spark.html

I ordered a new battery, figuring with solid voltage the bike should start up. I added the electrolyte and trickle charged the battery as per the manufacturers specification, installed it and the bike cranks over just fine but still doesn't start. Once I put the battery charger on, it fires right up. It will start off the battery for about five seconds after I shut it off, but any longer than that and it just cranks and cranks with no fire. The fuel pump is cycling fine.

Anyone??
 
#4 ·
12.7 VDC without the key on
12.5 VDC with the key on
11.6 VDC while cranking

I have found that once the bike has started on the battery charger, I can turn the charger off and as long as I don't turn the key off it will start multiple times. As soon as I cycle the key one time, it won't start on the battery again.
 
#3 ·
I will run the numbers, but I'm no stranger to working on bikes and I know what a weak battery sounds like. I bought a Yuasa battery which isn't the top of the line but a quality battery nonetheless.

I am guessing I have resistance somewhere, so I will be checking grounds. I also considered that the resistor on the ignition switch may be failing?
 
#5 ·
I thought perhaps the resistor in the ignition switch was causing issues, Kawasaki has a 100 ohm resistor that reduces the signal to the ECU down to about 6VDC so that you can't just twist wires together to steal the bike. Sadly for me, but good for the bike...the resistor tests good and I have 6.15 VDC at the ECU with a solid battery.

Now, that being said it doesn't start off the battery. When I hook up the booster the signal at the ECU goes up to about 8VDC and it then starts. Aha, you say! Maybe the ECU is needing more voltage for some reason. Perhaps, but when I shut the booster off and kill the engine withe the kill switch (not the key) it will start numerous times with only 6 VDC. Even less if I let the bike sit for 5-10 minutes. Once I cycle the key off and on again, no start until the booster is once again applied.

It's a head scratcher.....
 
#6 ·
You can charge a battery to 12 volts or even more and still not have enough amps to get the engine running. Yeah the engine is cranking over, but does the battery have enough amps to do that as well as run the pump efficiently and create enough spark to get it going? If it works with the jump pack and not just on regular battery then it's more than likely the battery doesn't have sufficient amps to get it running.

It seems like you haven't really fixed your issue with spark, according to the other thread you have. It's possible you have a parasitic draw when the bike is off which could be pulling the amps down while the bike is off, or maybe the new battery isn't any good. It's not an uncommon thing. I don't know what type of multimeter you have but running a parasitic draw test would be pretty easy if it has a min/max setting that it records.
 
#7 ·
OK, the post above was my point.
But this post from you -

"Perhaps, but when I shut the booster off and kill the engine withe the kill switch (not the key) it will start numerous times with only 6 VDC. Even less if I let the bike sit for 5-10 minutes. Once I cycle the key off and on again, no start until the booster is once again applied."

So here is a troubleshooting thing.
Start the bike with the "booster". and then only use the kill switch, DONT turn the key.
When running what is the battery voltage.
After the kill switch is used and key still on what is the battery voltage.
AND after 5 minutes after the kill switch and the key still on what is the battery voltage.

AND maybe try this -
Start the engine, leaving key on use the kill switch, then with key still on remove positive wire from battery.
Wait a minute.
Reattach the positive (key still in on position), and try to start with no booster.


Until you make absolute sure that the battery is good nothing else matters, yet.
 
#8 ·
It would be nice if folks read what he says before making comments. He clearly stated that it WILL crank over and over on the battery (no booster) once cranked with the booster and shut down with the kill switch, but with key still in the on position. If it will then crank over and over without the booster and until the key is turned off, it is probably not the battery.
@tntmo, when you checked the voltage to the ecu, did you check it after turning the key on, but before starting with the booster? Did you check it after starting with the booster, but only shutting down with the kill switch? Were the voltages between those two checks the same? I can't explain how it could be happening, but it sounds to me like you have a problem with the key switch. Something obviously changes with turning the key off.

I can't see how what you describe would happen if the starter button was dirty, but you might want to clean it. Some weird things can happen when those get dirty.
 
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#10 ·
Thanks for the reply. I did do the ECU voltage checks (on the gray wire) from the key switch and at the ECU. Without the booster it was just over 6VDC, whether it's initially turning the key on without the booster attached (which means no start) or after getting it started on the booster and then shutting it off (which means it starts every time). Crazy, right??

It's almost like there is a switch or relay or something that gets energized once the booster is applied and it stays on until the key is cycled off. Or the ECU needs an initial shot of more voltage to get going initially and once it has started it's ok with lower voltage? It doesn't make sense.

I have already cleaned the starter button once, guess I could check it again. This bike has higher miles (65,000) but it doesn't seem like it was abused.



It would be nice if folks read what he says before making comments. He clearly stated that it WILL crank over and over on the battery (no booster) once cranked with the booster and shut down with the kill switch, but with key still in the on position. If it will then crank over and over without the booster and until the key is turned off, it is probably not the battery.

@tntmo, when you checked the voltage to the ecu, did you check it after turning the key on, but before starting with the booster? Did you check it after starting with the booster, but only shutting down with the kill switch? Were the voltages between those two checks the same? I can't explain how it could be happening, but it sounds to me like you have a problem with the key switch. Something obviously changes with turning the key off.

I can't see how what you describe would happen if the starter button was dirty, but you might want to clean it. Some weird things can happen when those get dirty.
 
#9 ·
I have used three different batteries on this bike so far, actually four now that I'm thinking of it. First one was the battery I got with the bike, unknown age but it cranked over the bike fine. I will consider that battery not to be great, even though it charges to 12.6 VDC and cranks the bike over fine for several attempts.

Second battery was a lithium that I have here in the garage, it's smaller dimensions but has more CCA than the stock battery. I have used this battery to start my buddies Harley, it's quite powerful and is in good condition.

Third battery was a mistaken order, I ordered a YTX 16 BS-1 but it has incorrect posts for the Vulcan. I still charged it and tried to use it, same thing happened with that battery. I sold it to a friend after ordering the current battery

This battery is a newly purchased Yuasa YTX20CH-BS that I filled and charged as per their recommendations.

I'm pretty sure it's not a battery problem.

The battery had 13.08 VDC right now
Turn the key on and it dropped to 12.95, cranked and cranked with no start. Fuel pump is priming just fine. Voltage during cranking is between 11-11.5
Applied the booster at 40 amps, bike started immediately. Stator puts out 13.75 VDC at idle. Removed the booster, shut off the bike at kill switch leaving the key on. Battery is holding at 12.9 VDC. Starts immediately off the booster. Several times.
Shut off the bike at kill switch, left the key on, all lights on for five minutes. Battery is at 12.5 VDC. Started immediately.
While running, I removed the ground and the bike died. Reinstalled ground. Bike didn't start.

I don't believe it's a bad battery. Check this out.....if I turn on the key, then turn on the booster the bike will not start. If I turn the booster on first, then turn the key on, starts right up.
 
#14 ·
With meter set for DC volts, place negative lead on battery negative post. Under gas tank you will see ignition coils, there is a red w/blue trace wire that supplies power to them. VOM positive lead to this wire at ignition coil connector. Turn on ignition switch, should be see battery voltage. This is without a booster connected, just the battery. Next push start button and see if voltage remains the same.
 
#15 ·
Voltage at the coils is the same as battery voltage, at this point about 12.6 VDC.

When I push the start button it drops slightly to 11.7 VDC

When I put the booster on 40 amps, voltage goes up to about 14 VDC, press the starter button and it drops to maybe 12 and the bike starts.

Then I shut off the booster, have the same numbers as the top two and it starts every time.
 
#19 ·
Well I'm glad you're convinced about the battery. Now go ahead and be awesome and help me solve this! I'm a pretty decent old school farm mechanic with no official motorcycle training but I can hold my own and pride myself on solving problems.....and this one is a real wild one. Keep up the suggestions!


When you attempt to start the bike (not on the booster, just battery), and it does not start, does the headlight come on and remain on until switch is turned off?
Yes, the headlight relay works on just the battery.
 
#20 ·
Things that have been eliminated as problem: battery, ignition switch, start stop switch, dfi relay, ignition coils, ignition pulse triggers, and
junction box. The variable here is the igniter. Although it seems to function once the bike is started and continues to until the ignition switch is turned off, I would not eliminate it until I was able to try another for testing. There are no test procedures for an igniter. Perhaps you can find one for a loaner. The part # you need is: 21175-0048. '05 ~ '08 Nomad. I would suggest if you have not already done so, disconnect and inspect all connector plugs, look for bent or damaged pins, use a dielectric grease and reconnect . Good luck, and keep us posted with results.
 
#21 ·
I couldn't sleep last night thinking about this damn thing. I was looking up the ignition system, and igniter was one I was reading about. It's built into the ECU....and I have been suspecting the ECU. I see a local Nomad for sale, would perhaps offer the guy some money for a few minutes of testing. I would think a VN1600 ECU of the same vintage would work as well?

I'm also looking to checking the crankshaft sensor. Not much else out there to check.
 
#23 ·
Haha, yeah I would think I could eliminate a lot of things since it starts and runs. :laugh2:

I even found a junction box in my stash of parts from a late 90's Ninja 250, plugged that in and no change. Funny how it was plug and play from such a different model.
 
#29 ·
I had considered this. I have a spare ignition without a key, I was just going to cut the wires and make it into a jumper plug. If I do that, I could just wire in a different resistor. The only reason I don't think that will matter is that the bike starts with the 100 ohm resistor after the initial start. But it's cheap enough to try before spending money on an ECU.


Also, there is an orange colored joint connector (grounds) near the battery.
Check it for signs of burning. These can cause all kinds of weird issues if they have been overheated.
I had looked at this, it doesn't appear to be in bad shape but I saw posts about it online. I'm considering doing the ground block repair I have seen. It's just another thing that doesn't cost much and can be eliminated as a suspect.

Thanks for the ideas, I appreciate the input.
 
#30 · (Edited)
The reason I suggested the resistor is there is a possibility that the anti-theft incorporates an electronic latch that, once set, will remain until key off.
If the circuit is border line with the charger pushing it over into latch condition but the battery, alone, does not, then the resistor change may show that up.
 
#31 ·
The reason I suggested the resistor is there is a possibility that the anti-theft incorporates an electronic latch that, once set, will remain until key off.
If the circuit is boarder line with the charger pushing it over into latch condition but the battery, alone, does not, then the resistor change may show that up.
Well I have had the exact same thought so I do appreciate it. I'm going to try it before picking up an ECU.
 
#32 ·
I soldered in a 75 ohm resistor, it only brought the voltage up to 6.5 and didn't start the bike. I didn't have many other choices for resistors, so I wired three 20 ohm resistors together for 60 ohms total, brought the ECU voltage up to 7.5 or so, no change.

I picked up a can of electrical contact cleaner, sprayed out the connections on the ECU and looked for any obvious damage on the pins and connectors but none obvious.
 
#34 ·
You said earlier that the voltage to the ECU was 8.0 V with the booster. One or two of those 20 ohm resistors should get you there. If you can at least crank it with the lower resistance allowing 8 plus volts to the ECU, it would seem to point very strongly at it being the anti-theft circuit in the ECU.
 
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#33 ·
I keep thinking that maybe there is a wire or connection that has corrosion or resistance in it that is causing this issue, but it doesn't explain why it would start on the booster and then start again and again on just the battery after the initial start until the key is cycled. There must be some circuitry in the ECU or something.....I haven't found anything else in the wiring diagram that it could be.
 
#36 ·
Went down to 40 ohms, got 8.4 VDC to the ECU and no start.

I'm wondering if there's something else I'm missing? I see wiring harnesses on Ebay are cheap enough. I ordered a tip over switch for $5 as well, just in case that's having some sort of effect on this thing.
 
#37 · (Edited)
I'm still not quite ready to order an ECU. I have been doing a lot of resistance checks, etc.

The grounds on the ECU are supposed to read continuity ( 0 ohms) on pins 10, 20, 32 and 42 to the battery ground terminal with the key on or off. They are reading low ohms, 0.5 or so with the key off but all of them are reading about 82 ohms with the key on. That doesn't change with the booster on, but the bike starts.

I was reading the resistance at the orange ground joint connector, thinking about changing that out. With the key off, they are all under 1 ohm. Turning the key on the resistance jumps to about 200 as the pump cycles, then drops to 82.

I checked the resistance from the main ground wire from the frame to the battery, zero resistance.

All this said, adding the booster changes the resistance with the key off down to zero, but with the key on/booster on the numbers are higher and the bike starts. Then shutting off the booster, shutting off the bike with the kill switch and the resistance numbers are the same as before, the bike starts off the battery. Until the key is cycled off and on again.

Mind blown!

I have a couple YouTube videos but I don't know if it's cool to post them here. Someone let me know and I will put up the links.
 
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