No spark....again :(

Energy One

jarnett

Active Member
Well guys not long ago (maybe 6 months) I had a "no spark" issue. After a few simple tests I guessed the cam sensor was bad. Ordered a new one from Curtis and installed it and everything was fine. Until now...last week I ride to the bar and when I came out to leave my bike would start. I quickly realized there was no spark after pulling the wire and grounding it to the motor while turning the motor.

As far as the ignition module, the red light comes on when I turn the key on and flip the switch to run. When I press the starter button the red light blanks once and stays on. Seems like the cam sensor again but now I'm wondering why the sensor would go bad again so soon. Anyone have any comments or ideas? I want to order the sensor but I want to continuity check it first and I would like to know if there is any other underlying issues that's causing my sensor trouble. Any help or feedback would be much appreciated I'm hoping to get her running to get to Daytona soon thanks!.
 

Sven

Well-Known Member
Let me see if I understand this. 6 months ago, you changed the cam sensor, it ran for 6 months until now, correct?

A sensor makes a square wave so you want to run the volt meter to volts if not millivolts. So remove the sensor wire connector, hook the ohm meter leads to either prong, meaning, it makes a/c volts so it does not matter which prong is posi or neg.

WATT you want to see is to compare both cam sensors on the bench now. Do both read the same? If a new one comes, compare all 3. Do all 3 have the same resistance? Then, it's not the cam sensor.

When you plugged in the 2nd sensor, the bike ran, right? Someone said their cam wire came loose twice. So you might conclude that if all 3 sensors have the same resistance, you plugged in the 2nd sensor and it ran, then it happened to stop now, watt are the odds you mess with the cam sensor wires on the harness side and make sure the integrity on the cam connector side has integrity too.

Until the 3rd cam sensor comes, is this a harley aftermarket cam sensor? Why not see if you can swap it out for a harley sensor, not some asian knockoff?
 

NZBigDog

Member
Yep, agree, if light is ON (flashing at a high rate), then check coil....if its one of the green coils, check the housing isnt cracked and it isnt shorting on the alloy cover
 

jarnett

Active Member
I have a red light but it does not blank when pressing the start button like it did before. Guess I'll have to work on it next weekend I got the call to travel to Georgia to work the week.
 

jarnett

Active Member
Ok checked connection near the pickup, red is 12V to pickup, confirmed 12V to pickup, green is ground and has cont to ground. blk would be signal. there is continuity from connector near ignition module to connection near pickup.

Key on> ignition module red light on
Press start>motor turns, red light on module stay on. (NO BLINKING) no spark
While pressing start> No voltage pulse or anything on the signal wire

I pulled the sensor plate, no gunk, checked the connectors and such, seem to be fine

Seems to me I need a new sensor again. Just confused why this one did not even last a year.

Wondering if I should upgrade the ignition. I remember someone telling me the electronic single fire ignition kits when the electronics on the plate may be a bad idea with the heat thats in the cone area where it mounts. Any opinions or experiences?

Is the standard pickup and ignition module more reliable? I just want to a solid spark all the time.

Curtis? Hit me up bud gonna need a part or two it seems. jarnett1979@gmail,com
 

jarnett

Active Member
Let me see if I understand this. 6 months ago, you changed the cam sensor, it ran for 6 months until now, correct?
correct

A sensor makes a square wave so you want to run the volt meter to volts if not millivolts. So remove the sensor wire connector, hook the ohm meter leads to either prong, meaning, it makes a/c volts so it does not matter which prong is posi or neg.

I checked continuity for all 3 wires from the connect near the sensor to the connector near the ignition module. Low resistance and ring out clean. Checked and confirmed 12V at the sensor side of the connection nearest the sensor. Green wire has continuity to ground. No pulses from signal wire when motor turns

WATT you want to see is to compare both cam sensors on the bench now. Do both read the same? If a new one comes, compare all 3. Do all 3 have the same resistance? Then, it's not the cam sensor. Ill have to find the old sensor and compare the two, havent ordered a new one yet.

When you plugged in the 2nd sensor, the bike ran, right? Someone said their cam wire came loose twice. So you might conclude that if all 3 sensors have the same resistance, you plugged in the 2nd sensor and it ran, then it happened to stop now, watt are the odds you mess with the cam sensor wires on the harness side and make sure the integrity on the cam connector side has integrity too. From ignition module to sensor there is one connector and one set of crimped connectors I installed with new sensor last time. I am sure at this point the integrity of these conductors are good from sensor to ignition module

Until the 3rd cam sensor comes, is this a harley aftermarket cam sensor? Why not see if you can swap it out for a harley sensor, not some asian knockoff?
The last one came from WSW, cant remember the brand. I assumed it was decent. Thinking of possibly upgrading to one of the twin tech electronic programmables. More possible issues or worth it?
 
The green wire is the signal wire on your sensor plate. Pull the coil and check the windings resistance with an ohmeter...should be about 3 ohms on the primary windings. Not sure what the secondary windings (where your spark plug wires plug into) are supposed to be, but any Pre-1999 Harley manual will tell you (If you still have the factory dual fire coil) Obviously, if you find an open circuit, you have a bad coil for sure. Often times we will find one of the wires going to the coil broke (bad crimp). I'm assuming you have a 107" on your 03.
If that's the case, you're limited to either running a sensor plate, and external ign module, or a sensor/plate ign mod combo. Either way, they're both in the camchest and prone to thermal failure..I can't think of any way around it. We like the Crane Hi-4N. The Twin Tech is a good option as well. C.A.Jones V-Twin | Custom Builds, Parts & Service
 

jarnett

Active Member
The green wire is the signal wire on your sensor plate. Pull the coil and check the windings resistance with an ohmeter...should be about 3 ohms on the primary windings. Not sure what the secondary windings (where your spark plug wires plug into) are supposed to be, but any Pre-1999 Harley manual will tell you (If you still have the factory dual fire coil) Obviously, if you find an open circuit, you have a bad coil for sure. Often times we will find one of the wires going to the coil broke (bad crimp). I'm assuming you have a 107" on your 03.
If that's the case, you're limited to either running a sensor plate, and external ign module, or a sensor/plate ign mod combo. Either way, they're both in the camchest and prone to thermal failure..I can't think of any way around it. We like the Crane Hi-4N. The Twin Tech is a good option as well. C.A.Jones V-Twin | Custom Builds, Parts & Service
Thanks, Ill check the coils. Not sure why I haven't done that yet, I have both sensor plates on the table. Getting different readings on each.

Yes I got the 107 with factory dual fire. Thanks
 

jarnett

Active Member
Thanks, Ill check the coils. Not sure why I haven't done that yet, I have both sensor plates on the table. Getting different readings on each.

Yes I got the 107 with factory dual fire. Thanks

Primary side shows 3.6 ohm, secondary side shows 11.66k ohm.

So should the secondary side be so high? I probed without the plug wires. Sounds open to me. Bad coil?
 

jarnett

Active Member
Primary side shows 3.6 ohm, secondary side shows 11.66k ohm.

So should the secondary side be so high? I probed without the plug wires. Sounds open to me. Bad coil?

Ok found out secondary should be around 13k ohms. So Im close. Guess the coil is good
 
3.6 is a little high for the primary side...I wouldn't rule it bad or good just yet. If you're not in a hurry, I could ship you a used coil Monday just to use as a tester. I think we have a few of the small ones Big Dog tried to use on the early 2000-2002 or so models, and we've probably got some with busted mounting holes. I wouldn't run it as your primary coil, but it would work for a tester for you. C.A.Jones V-Twin | Custom Builds, Parts & Service
 
Jason, I went out to the garage and found a couple of old Dyna coils laying around. They're close to the range you're talking about. I think your coil is fine. We're back to sensor plate or ign module... I can't remember on the 03's if the Thunderheart ign module red light flashed or just stayed solid red. But if you're not up and running come Monday, call the shop and I can tell you how test the module. Good luck man. C.A.Jones V-Twin | Custom Builds, Parts & Service
 

DRBarnhart

Insert title here...
I can't remember on the 03's if the Thunderheart ign module red light flashed or just stayed solid red.
The ignition module LED should blink as the engine turns over. Since this one doesn't, it seems the cam sensor is bad again. If you want to test it (only takes a minute or two)...

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. (Any resistance is "bad")
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.


Dennis
 

jarnett

Active Member
The ignition module LED should blink as the engine turns over. Since this one doesn't, it seems the cam sensor is bad again. If you want to test it (only takes a minute or two)...

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.

No continuity from any wire to the plate

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. (Any resistance is "bad").

shows 20+ Mohms. thats open enough for me i think

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.

showing about 260 kohms here. close enough?


Dennis
thanks for all the help guys im thinking i may just go ahead and get the sensor. sucks ill be working out of town all week again so ill be unable to install until next weekend. really considering spending the money on an electronic single fire upgrade. will I notice a nice improvement there over stock?
 

jarnett

Active Member
Jason, I went out to the garage and found a couple of old Dyna coils laying around. They're close to the range you're talking about. I think your coil is fine. We're back to sensor plate or ign module... I can't remember on the 03's if the Thunderheart ign module red light flashed or just stayed solid red. But if you're not up and running come Monday, call the shop and I can tell you how test the module. Good luck man. C.A.Jones V-Twin | Custom Builds, Parts & Service
thanks so much for your input man i truly appreciate it:up:
 

DRBarnhart

Insert title here...
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. (Any resistance is "bad").

shows 20+ Mohms. thats open enough for me i think
"Open enough for me" doesn't count, sorry. :lol: Your meter should be reading the same thing it does when it's ON and the probes aren't touching anything.

Although it's a very high resistance it's not an "open" and I'd say your sensor is bad. :down:

Dennis
 

jarnett

Active Member
"Open enough for me" doesn't count, sorry. :lol: Your meter should be reading the same thing it does when it's ON and the probes aren't touching anything.

Although it's a very high resistance it's not an "open" and I'd say your sensor is bad. :down:

Dennis
agreed. bad sensor. I do industrial electrical work so I use a fluke 87 digital multimeter. thanks for your help!
 

kennycarr

Member
What does it mean when the light on my ignition module comes on just for a second then goes off? Not getting fire
 
my 07 k 9 never has spark when its cool out side. i just put a switch from battery to coil then after it warms up i turn switch off. been doing this for about a year and works like a champ.
 
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