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Hey I was curious, on my way across Canada and the bike has died and now I have no spark. Tested a bunch and I’ve found that the pickup coil’s resistance is within the 100-150 ohms, and no continuity to ground, but I still cannot measure any AC voltage coming out of the sensor. I removed the cover and when placing my two leads on the sensor wires and placing a wrench in front of the sensor I get no fluctuation at all in the AC mode. From my understanding these sensors produce their own ac voltage when a ferrous object comes into close proximity to it, wondering if I’m on the right track. Just seems weird to deem the sensor faulty when the resistance values check out. Any help would be appreciated. Also I’m north of Belleville if anyone has a sensor kicking around close by?
Thanks in advance
 

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is it fair to assume you've check all the wiring and switches? The pick up coil can't be tested that way. Now that its out all you can check is ohms and make sure it isn't shorted. Dynamic testing requires it to still be installed.

If you check all the ignition system wiring and components (except cdi and ignition coil secondary) from the gang plug where the CDI plugs on you eliminate a lot of things fast. This method includes testing all the other coils wiring and switches en mass. Checking everything at that plug rules out a lot of things fast and gives you a broad view and usually a direction to investigate. If you find nothing wrong it points towards the CDI failing (due to high operating voltage, CDI's are prone to fail more often than 12 v dc ignitions).

To test everything completely you have to have a peak volt meter or adapter like this and the knowledge to use it efficiently. (always used as a parallel connection to the system, never in series)

you have to be able to read a wiring diagram as well.

Some other fellas here will chime in with common shorts on the Gen 1(i hope), like the kill switch issue if memory serves
.
 

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Hmmm, ya I checked resistance values of both exciter coil and pickup coil from the plug at the cdi box and both are within spec. Checked for continuity to ground on both coils and both have zero continuity. Checked the switches and they are all functioning properly (no continuity to ground when trying to run). I can read ac voltage out of my exciter coil when turning over but every way I’ve tested I cannot get a voltage signal into the cdi from the pickup coil which led me to believe that was the problem, but maybe for some reason like you said if cannot be tested this way. That would then lead to my cdi being shot as I have no voltage coming to my ignition coil at all when trying to start
 

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I think dynamically testing the pickup coil is a sort of, "chicken or egg" thing!

The electrical output of the pickup coil can't be produced unless the engine is running; if the coil is unserviceable, the engine won't run.

Could the spark plug be removed and the engine turned fast enough with the starter to register a pickup coil output (AC pulse)? Don't know.
 

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You should get some measurable pulse, but you need an analog meter to see it. Most digital meters don’t refresh fast enough.
 

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An analog meter is needed to test for the VERY Low ac voltage output of a pick-up coil. I've seen as low as .5 vac at cranking speed on other engines. I've No idea as to any specifications at cranking speed.
With an Steel end wrench swinging back and forth 2 Post-It notes above the magnet of a dismounted pick-up coil, you should be able to see an Analog meter Needle TWITCH. The faster the wrench movement the higher the twitch. I believe this speed of signal (voltage increase) is what advances the timing as RPM increases.
 

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With an Steel end wrench swinging back and forth 2 Post-It notes above the magnet of a dismounted pick-up coil, you should be able to see an Analog meter Needle TWITCH. The faster the wrench movement the higher the twitch. I believe this speed of signal (voltage increase) is what advances the timing as RPM increases.
I thought the magnet (and its consequent magnetic field) was within the flywheel/rotor timing lump; not the pickup coil. Thus, an ordinary un-magnetized wrench might not generate any measurable electrical output from a pickup coil. no matter how fast the wrench moved or how thin were the Post-It notes.

In normal operation, I think the "magnetic lines of force" from the rotating permanent magnetization within the flywheel/rotor timing lump are "cut" by the coil windings with each rotation, generating electrical pulses.

DISCLAIMER: Speculation only; never tried myself measuring voltage from a pickup coil or observing an analog meter's needle as an un-magnetized piece of steel passed by the coil. Pass a MAGNET in near proximity to an operational pickup coil; and . . . some electrons (and holes) oughta flow, I'd think.

As to spark timing advance, my unproven, undocumented theory assumes the magnitude of the timing pulse rises with rpm, resulting in producing an earlier angular voltage threshold level firing the spark sooner, thus advancing ignition timing. I know, I know; that's only my theory, may not work that way at all.
 

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When we dis-assemble these engines to say install a doo-hickey & torsion spring, we will see ferrous metal paste sticking to the side of the pick-up coil & the Inner diameter of the flywheel. But no ferrous metal particulate on the shiny clean exterior of the flywheel (and I've never understood why).

And ask many owners/mechanics just how sharp some areas of the inner diameter of the flywheel can be, as they try to wipe out the ferrous metal paste with a bare finger?
 

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When I was mucking about with the CDI unit in a fruitless attempt to understand its inner workings, I was able to induce a voltage in the pickup coil by waving a wrench at it. Good Neighbor Ray thought I was quite daft until I explained what I was doing. After that, he thought I was normal daft.

The pick-up coil is a magnet with a coil wrapped around it. The exposed nubbin is magnetic. The thing on the rotor that I have variously called a reluctor, a transluctor and a "thing on the rotor" performs the same function as waving a wrench at the coil as it passes within a wee fraction of a millimeter of the nubbin on the coil.
 

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Maybe . . . magnetized wrench?

My belief system holds the flywheel/rotor possesses magnetism (hence, the alternator sometimes appears named, "magneto" on Kawasaki wiring diagrams).

I've thought the magnetic field of the flywheel/rotor passing by the pickup coil generated a pulse; said pulse triggering a thyristor (silicon-controlled rectifier, or SCR) discharging a capacitor (Generation 1 CDI) across the primary windings of the ignition coil, producing a high-voltage spark from the secondary ignition coil windings.

Such notions may only be legend gleaned from superstition and overhearing murmuring of the inebriated around the campfire; no validity whatsoever claimed.
 

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No. My wrenches are not magnetized.

But, I might suggest that a properly polarized (North vs South) magnet waved across the pick-up coil would probably show a higher VAC reading, than a common non-magnetized end wrench. :)
 
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Maybe you've got something . . . airport security detectors probably register both magnetized and non-magnetized guns and knives.
 

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Google tells us, several ways exist to skin the cat (of crankshaft position indicator).

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How A Crank Sensor Works
There are different set ups for crankshaft sensors, but they tend to work on principles of magnetism. Many crankshaft position sensors are a type of electronic sensor known as a Hall effect sensor. A Hall effect sensor produces electricity in when it is exposed to a magnetic field. In a crankshaft position sensor, a toothed wheel, spinning with the crankshaft, disrupts the magnetic field. That produces a pattern of on and off switches in the Hall Sensor that the ECU can interpret as the crankshaft speed. The faster the sensor is turning on and off, the faster the crankshaft is spinning.

While these Hall effect sensors give a digital signal, some crankshaft position sensors produce an analog signal. They still operate on magnetism, though. The sensor produces an electrical voltage based on fluctuations in a magnetic field. The fluctuations are caused by the movement of metal pins in the crankshaft. Faster spinning means more fluctuations and more voltage.

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I learned more about, "Hall effect sensors," than I ever cared to know, wrestling with the kickstand sensor on my KTM690.

Tom alludes to a, "reluctor:"

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Reluctor rings[edit]

The reluctor ring on an ABS-Sensor
To measure angular position or rotational speed of a shaft, a toothed ring made of ferrous material can be attached to the shaft. As the teeth of the rotating wheel (or other target features) pass by the face of the magnet, the amount of magnetic flux passing through the magnet and consequently the coil varies. When the gear tooth is close to the sensor, the flux is at a maximum. When the tooth is further away, the flux drops off. The moving target results in a time-varying flux that induces a proportional voltage in the coil.

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So, . . . ain't sure how the KLR pickup coil works. Oh for the days of points-and-condenser ignitions!

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EDIT: Click here, look at the pictures in Post # 1 on this thread to see compelling evicence indicating pickup coils are MAGNETIZED:

 

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My bike died in NM on day 2 of a week long trip. I brought it home, Installed a new ignition box, no go. I installed a new stator and it started right up.

I left the pickup alone since it worked, pretty sure I still have it.
 

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a peak volt adapter would have sorted this fast as it tests the output of the coils while cranking with the spark plug out and grounded. Very glad you have it sorted. happy motoring
 

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Discussion Starter #16
Thanks for the insight I was able to replace the CDI and be on my way again. When my dad tested my pickup sensor at home of my 2004 klr the multimeter would not register an A/C voltage with a wrench either. So it must not be able to read the pulse as you guys are saying
 

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Thanks for the insight I was able to replace the CDI and be on my way again. When my dad tested my pickup sensor at home of my 2004 klr the multimeter would not register an A/C voltage with a wrench either. So it must not be able to read the pulse as you guys are saying
glad you're motoring again. Peak volt adapter, only way ;)
 

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this thread makes me chuckle , out loud
OK, what Should the Peak AC Voltage of the Pick-up coil (crankshaft position sensor) BE?
Show me the specs.
 

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no specs specifically from Kawasaki but the output of CDI systems is similar across the board so specs can be extrapolated from other applications as the manufacturers are the SAME
 
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