Crankshaft Position Sensor : V-Twin Forum: Harley Davidson Forums

PhilRKC · 03-04-2007, 05:08 PM

It has been some time since i have been to this site. Originally i got a lot of good information and it helped in the purchase of my 2003 Road King Classic.
Since then have enjoyed the bike. Did Texas to Sturgis in 2005 and looking for more of the same.
Anyway, the reason for the thread.
I changed the oil yesterday, the oil filter was VERY tight. As a result all the filter wrenches i had would not get it off, so i used to old fashion method, a screwdriver........ As a result of the damage to the oil filter, the wires to the Crankcase Position Sensor (CPS) were stretched..... possibly damaged.
When the oil change was completed the bike would not fire, it turns over, but not fire. The only difference in this oil change to any others was the stretched wires on the CPS. I have searched multiple locations and could not find the answer to my question.
What should the resistance be when measuring the wires to the CPS. I am getting 0, not knowing exactly how the CPS works, meaning is it normally open or normally closed (or otherwise), i am not sure if "0" resistance is good or bad.

The bike was running fine several hours prior as i took it for a run to warm up the engine and oil.

Any thoughts, or information on what should be the reading when testing the continuity of the CPS circuit, or anything else that may help resolve the problem is appreciated.

Oh, how do i pull the codes on the 2003 FLHRCI, do i need anything special to get this information.

Thanks in advance.

PhilRKC

jim t · 03-04-2007, 08:39 PM

Sounds like you severed the wires inside the insulation. A new sensor is about $50.00 here. The only electrical malfunction I have had on my bike and it did not go out completly just started running shitty. I can't tell you the ohm value of a functioning sensor but the one I removed reads open and was just functioning poorly. I have spoken with guys that do a lot of long distance riding and they say they always cary a spare. A tip on oil filter removal. When I run into a tight filter I use a large channel -loc plier and it has never failed me or caused any dammage. Cars, bikes, boats et al. Jim

AmarilloDano · 03-05-2007, 08:28 AM

I've come across a bad crank sensor before, it showed open on the ohm meter. The new one showed a minimal resistance, 3 or 5 ohms, if I remember right. After all, it's just a coil. Now don't go counting on my antique memory! It's had over half a century of abuse.

As for oil filters, I bought a nylon strap stlye filter wrench some years ago and haven't come across a filter that could whup me yet. A few that got a might crushed in the process, but they all came off in the end.

Ragnar · 03-05-2007, 10:52 AM

A screwdriver in the oil filter makes a nice mess, too, doesn't it? Your symptoms are exactly those of a bad sensor. Just replace it. I also agree with the giant channel locks if you don't have the right wrench.

Ragnar

PosseRider · 03-05-2007, 11:03 AM

Aww , but the strap is easier, You just use a rachet to turn. Dont have such a hard time getting that large channel lock in there.

PhilRKC · 03-05-2007, 05:52 PM

Guys,

Thanks for the responses, i had order a new sensor anyway. When something like this goes wrong you just have to look at what you were working on.

What better way to learn more about the bike, less the $50....

Will let you know the outcome.

Thanks again

PhilRKC

Ride · 03-05-2007, 06:00 PM

I just carefully pull my crank position sensor before changing the oil, wrap it in a paper towel and move it out of the way. Check J&P cycles...they make a filter wrench with a cut out in it to work around the crank sensor if you don't want to take it out.

I can tell you that when that sensor decides to quit your not going anywhere. Mine died 70 miles from home and cost me a tow. Lucky for me I had two weeks left on the extended warranty and got all but $100 back.

fuel · 03-05-2007, 08:40 PM

Hello all. I'm new to this forum and I don't own a Harley yet, but I'm looking to buy one soon. But I think I might be able to help out with this problem.

Like jim t said, I also think that you probably broke a wire. You can't check a the crank sensor with an ohm meter. The way to check it is with a digital volt meter. I'm not sure how many wires Harley uses for the sensor, but most sensors use three wires. One is a ground, one is power and the other wire is the signal wire. First thing to check is to see if your getting voltage to the sensor from the ECU (could be anywhere between 5 and 12 volts). Unplug the wires from the sensor and turn on the ignition. Then probe each of the wires to see if there is one of them that has voltage, if not there is a problem with the wires.

If your getting voltage then it could be the ground wire if it has one. If it has one then back probe the ground to see if it has resistance. If it has resistance then more than likely it is the sensor. But to make sure, plug the sensor back up and then you will need to probe the signal wire with the volt meter while you are cranking the motor. The voltage should fluctuate some where between 0.4 and 4 volts. But it could be different voltages, but regardless the voltage should fluctuate.

Good luck.

Joe

Fourcats · 03-05-2007, 11:23 PM

If you run the "codes" it should tell you whats up...

Having experienced the CPS going bad, I carry a spare.
You can take a new oil filter to a auto parts place and get a good {3/8 drive "cup style"} wrench for six bucks, they come in a bunch of sizes.

jim t · 03-06-2007, 08:49 PM

You know, I did that but it doesn't clear the sensor. What I intended on doing is taking my die grinder and cutting a section of the tool off to get clearence. Even with that mod I suspect one would have to be very careful not to break the wires. Jim

Fourcats · 03-06-2007, 09:05 PM

Its easy to pull the CPS {as mentioned} and move it out of the way while changing the filter. Don't over tighten the filter or the screw for the sensor...just snug them up.

berserker · 03-10-2007, 09:33 PM

I troble shoot elec systems for aliving, 125vdc, I have learned there are no coicidences. I used to tell myself, everything has to die someday, that has never been true. Of course first time for anything.

What about elec manual? I got one but haven't looked at. Hard to thumb through. If this has not reslved it self, by the time I sober up,I will look.

I have nicked mine a few times when chageing oil, so far so good. For $50, change it, one less thing to worry about.