NO SPARK - Troubleshooting Tree

[Moespeeds]

I see alot of posts from guys having electrical breakdowns. I figured I'd post a troubleshooting tree for this type of problem, maybe we could sticky it? Feel free to add or correct:

Symptom: Bike randomly quits or will not start

First thing to do is verify that fuel is getting into the carb. Once this is verified, chances are it's electrical.

If the engine is not cranking:
Check your battery voltage (12.8)
Check for an indicator light on your EHC when the RUN button is pressed
Check your key switch
Check for 12v going to the small starter wire plugged into the starter solenoid (usually GREEN)

If you have 12v going to the starter when START is pressed, then you probably have a bad starter or battery.

To test the starter:

How to check your starter solenoid

Open the starter, clean the contacts, and try again.

If the bike cranks, but won't fire:
Check for spark. Pull both plugs or use a spare plug. Pull both plug wires, plug one spark plug in, and crank the motor while grounding the threads of the plug on the bike. You should see spark. See the drawing below:



If you have spark, it is most likely a fuel problem.

If you don't have spark:
Make sure you have 12v to the coil. The coil should get 12v when you press the RUN button.

If you have power to the coil, but no spark, check your plugs and plug wires. You may also have a bad coil.

If you have no power to the coil:
Check for 12v down at the timing pickup when RUN is pressed. (2005 and up have no timing pickup down there, skip this step)

If you have power to the timing pickup, but no power at the coil, most likely the pickup is bad. Double check to make sure you have no power to the pickup, and no power at the coil. When you press RUN, the pickup sends 12v to your coil. This is a $30 part at any Harley dealership, but will need to be cut from the harness and soldered back in. If the bike randomly dies, then starts again after cooling down, this usually means a bad pickup. Remove the timing cover, start the bike, and run a hairdryer on the pickup. If the bike dies when it heats up, it's bad.

If you have no power to the timing pickup, check for a light on the ignition when RUN is pressed, and check to see if the ignition is sending 12v down to the pickup. Also check your EHC. One or the other is likely to be the problem at this point.

Here is a thread on how to use a multimeter:

http://www.bigdogbiker.com/forums/te...-week-2-a.html

[lee]

good post Moe. I would add that when you pull your spark plug leads, the one you are not using should be grounded.

[Slider]

Good post Moe. And don't hold the plug or sparks will shoot out your ass.

[Oscar Maldonado]

Originally Posted by Slider

Good post Moe. And don't hold the plug or sparks will shoot out your ass.

I've been there - Done that!

[Moespeeds]

Figured I'd add this from DRBarnhart:

I've posted this a couple of times...

How do you test the cam sensor to make sure that is the problem.
1. Disconnect the cam sensor from the ignition module.
2. Take out your trusty multimeter and set it to the RX1 scale.
3. Now while touching the sensor backing plate with the negative meter lead touch the positive meter lead on each of the three wires of the sensor connector (red, black, & green). If you get continuity from the backing plate to any of them the sensor is bad.

If it passes the first test...
1. With your meter still at the same settings touch the positive meter lead to the green wire and the negative meter lead to the black wire. If you get an "open" it's good.
2. Then take the positive meter lead and touch the black sensor wire while touching the negative meter lead to the green wire. In this case an "open" is bad. A reading somewhere around 300 - 750 Kohms is what you're looking for.

[Moespeeds]

Any way we can get a sticky on this?

[Throttle Jockey]

Originally Posted by Slider

Good post Moe. And don't hold the plug or sparks will shoot out your ass.

And on a similar note with the spark plugs out you can look closley into the hole and tell if theres gas coming out!

TJ

[Five Five]

Thanks Moe ....hit you with a little "Rep Power"


"Five"

[MARV]

Originally Posted by Five Five

Thanks Moe ....hit you with a little "Rep Power"


"Five"

thats funny!

one of the guys with the most talent has minimal rep.

you go MOE! couple more ground up builds and you might get some respect around here!

[Ray]

Great post, always appreciated, already knew not to hold sparkplug from experience ! Watching someone else. like peeing on electric fence!! Talk a friend on mine into doing that ,,

Ray

[Moespeeds]

LOL thanks Marv, but my friends have the talent, I just listen well. I don't really know what the rep thing does, but unless I get some kinda prize, I'm not sweating it. Hope all is well up there, we gotta get together for a drink soon. I've been threatening Staffy for months.

[DRBarnhart]

Originally Posted by Moespeeds

Figured I'd add this from DRBarnhart:

I've posted this a couple of times...

How do you test the cam sensor to make sure that is the problem.
1. Disconnect the cam sensor from the ignition module.
2. Take out your trusty multimeter and set it to the RX1 scale.
3. Now while touching the sensor backing plate with the negative meter lead touch the positive meter lead on each of the three wires of the sensor connector (red, black, & green). If you get continuity from the backing plate to any of them the sensor is bad.

If it passes the first test...
1. With your meter still at the same settings touch the positive meter lead to the green wire and the negative meter lead to the black wire. If you get an "open" it's good.
2. Then take the positive meter lead and touch the black sensor wire while touching the negative meter lead to the green wire. In this case an "open" is bad. A reading somewhere around 300 - 750 Kohms is what you're looking for.

Thanks for the quote Moe! I just copy and paste everytime this quesion gets asked!!!


Dennis

[Moespeeds]

So again, how do we get a sticky on this? Seems worth it considering so many guys have no spark issues, and I know I've hunted this thread down and hotlinked it a few times.

[bearman]

in the 2007 service manual, page 230, it says
"the best way to test the ignition module is by troubleshooting to eliminate everyting but the ignition module."

on the same page it also says
"the best way to test the ignition coil is by troubleshooting to eliminate everyting but the ignition coil."

not a boat load of help there, but the paragraph before the first one above, says the ignition module has three LEDs:
Red comes on when power is applied (key on and run switch pushed, one red LED on on EHC), then blinks when starting and gets signal from crank sensor.
Yellow and Blue blink when front and rear coil triggers.

On my 2006,the red LED kinda dimmed and got brighter when trying to crank, but never blinked all the way off (blue and yellow never came on) so I wasn't sure, but with the new crank sensor it blinked all the way of once then the motor roared to life. I was just trying to see if the LED blinked and it cranked. I had to take off the left oil tank cover to see the ignition LEDs.
I wasn't sure it was the crank sensor so I put the new sensor in just temporary, I left the old one zip tied into the harnes and just unpluged it and removed the sensor, then installed and pluged in the new one.
I was in the garage so it was easy to see the LEDs on mine, not sure how easy they would be to see in sunlight.

[jimizee028]

You Rock Moe.....