I have a 2000 Springer. It has been on a jack for a few days. In the last couple of days, it showed symptoms of not wanting to start. No issues before then. The battery is good and it is on a battery tender. Spark plug cables are new, as are the NGK plugs. The CV carb is getting gas. Plenty of good, clean gas in the tank. Today, it would not start at all, even after several tries. It cranks good. I removed the front spark plug and it was not producing a spark. What should I look for first, ignition module, coil, or something else? I don't know if this has anything to do with it, but both plugs showed that the center electrode was blackened on one side only, but not the other. I saw this after only one day. I have never seen this before. Is this a symptom of the coil going bad? This bike is new to me so I have no idea what all has been done to it.

 

Are you getting spark from the plug wires?
Start there and trace back.

 

I have a single fire coil (Harley-Davidson OEM 31655-99). I used a volt meter to check for Ohms on the primary and secondary terminals of the coil. I got a reading of 0.09 on both primary coil terminals. According to the Harley service manual, then specs should be between 0.5-0.7 ohms. Mine is slightly higher. That means the primary side of the coil appears to be okay. I also got a reading of 12.4 on the secondary terminals. The service manual indicates that the normal resistance range is from 5.5-7.5 ohms. Since my secondary terminal readings are higher, are they too high? I would tend to believe there is nothing wrong with the coil.

I Also tested both spark plug cables for continuity, and neither cable showed continuity. Both cables are almost new. I used a test piece of wire to test continuity, and to check my voltmeter's readings, and it checked out okay. I suppose the next step is to replace the spark plug wires. But how could both wires turn out to be bad?

 

I also checked for continuity between the secondary towers, and there was no continuity. I believe this means an open circuit ( a break in the coil winding)?

 

I was up thinking in my sleep about this. I just realized that because my coil is a single fire, that each one of the secondary towers fires individually, and therefore, they are not linked together as they would be in a double fire coil, which fires both cylinders at the same time, and therefore, there would not be continuity between the towers.

Also, I did the Ohms test of the secondary circuit terminals again, but this time, I took the readings by placing the multimeter probe (20K on the multimeter) from the 12v terminal B (center) to each of the secondary towers. This time I got 0.8 in each one. This confirms that the primary and secondary readings are within specs. So, this confirms to me that there is nothing wrong with the coil. Since neither of the spark plug cables had continuity, I will replacing those and see if the bike starts with them in place.

 

Test your crank sensor with a good meter on AC volts.

Another giveaway is if equipped with a tach you should see a cranking rpm (not sure on your model if you would physically see it or only on a scan tool)

 

My bike does not have a tach. I just installed new Screaming Eagle spark plug cables, and still, no spark. The coil is good, but it is not getting any power. I turned the key on and used a 12 volt tester on the middle terminal (B terminal) of the Molex connector, and I get no power. I checked the "ignition" fuse under the seat and it is okay. I looked at the section in the manual regarding crank sensors, but it does not include anything on diagnosis. Anything to do with crank sensors is way beyond my capabilities, but from what I have read on YouTube and other sources, none mention that the absence of spark is a symptom, or related to a bad crank sensor. So what else can I check?

 

If you do not have power to the coil that is obviously an issue. You posted you checked the coil, so I should not have assumed you checked power to it.

If you want to check the crank sensor unplug the crank sensor - hook meter leads to it. Set to AC volts. Must have MINIMUM 1V when cranking. It's in the HD Manual.

Handlebar switch is on - correct.

 

It turns out you were right. A bad crank sensor affects many difference components, one of the symptoms is that it affects the timing when the coil puts out a spark. My apologies. Since I got a good offer on a new HD OEM crank sensor, I am just going to go ahead and buy it, but I will test the old one anyway. Thanks for your help. I will post in a few days with the outcome.

 

Ok. I think if I did the test of the old crank sensor correctly, it is reading zero Vac. I set the multimeter to the lowest setting, 200 Vac. There are only two wires coming out of the crank sensor, a black and a red. I placed the red lead from the multimeter to the red wire at the Deutsch connector, and the black wire from the multimeter to a good ground source (not enough room in the Deutsch connector to hook up the black lead from the multimeter to the black wire). I then cranked the engine and got a zero reading, so if I did it correctly, that means the crank sensor is bad. I am still waiting for the new one to arrive.