Camshaft Position Sensor (CMP) wiring pigtail replacement
This is documentation of what I did to replace the wire pigtail for the plug to the Camshaft Position Sensor. This is a result of a thread I posted about a no start condition that I diagnosed to be a broken wire in the pigtail, probably at the connector. You can read that thread here.
I contacted Hellman Motor Company, a Ford and Toyota dealership in Delta, Colorado. A parts guy named Paul spent some time determining that there is no replacement part for this specific connector. However, Paul spent about 45 minutes to an hour looking through a book of every connector he could order, comparing them to a Cam Position Sensor he had in stock, until he came up with this one. There are two part numbers, WPT359 and 3U22-14S411-JCA. Googling the WPT359 part number told me I could have ordered the connector from Amazon for $28.81, but I chose to go ahead and pay Hellman Ford $43.19 for it, since they went to all the trouble to find it for me. Judging from the connector diagrams in my service manual, this is also the same plug for the Crankshaft Position Sensor (CKP), so this procedure would probably work for it also.
This is the connector in question. When I got the new one home, I compared it to the one on the truck and they are identical in every respect, except for the wire color. The new connector has two black wires, where the factory connector for the CMP appear to be red and orange.
The first thing I had to do was get the wires up where I could work on them. I followed the advice of taking the front wheel off to reach in and unplug the connector, then pulled the connector up as far as I could. Eventually I cut a plastic and metal clip that was about 6 inches from the end of the wire off and pulled the wire up from behind the thermostat housing, etc and got it up to where you see it in this first picture. I also had to remove the air filter and air intake plumbing up to the turbo, and the cold side CAC tube, in order to have access to the wiring loom from the top.
The first two pictures are where I started. My first inclination was to simply cut the wires off at the plug and connect the new pigtail. But I was concerned that the broken wire might be right at the plug. Or it might be right at the end of the wiring loom or even up the loom some. I decided that I wanted to unwrap the loom back about 6 inches and replace at least 4 inches of wire in the loom.
This will continue in the next post. Here are the first two pictures.
The next three pictures involve getting into the wiring loom in order to get to the wires. I very carefully cut and unwrapped the fiber tape that wraps the loom. You can see I've completed this in the first picture. Go slow and carefully cut and unwrap as necessary.
The next step is to pull the wiring out of the loom. You can see in the first picture I didn't get the last wrap of fabric tape off of the end. I carefully cut through that and pulled the wires out. You can see now they are wrapped in electrical tape. Very carefully unwrapping the electrical tape you will end up with what you see in the third picture. The shielding is aluminum foil and I was not able to remove the tape without removing the foil with it. I managed to save a couple of inches of foil at the end. You can also see the bare wire that is the ground wire. This grounds at the PCM and runs the entire length of the loom. It contacts the foil all along and makes the ground shield. We will repair the shield in a later step.
The next picture was taken just after the "Oh ****, there is no going back now moment." I cut the connector off about 4 inches from the plug. I trimmed excess wire off of the new connector, so that the finished product would as long as the original and stripped the ends to prepare for soldering.
You may notice that I had the original connector laying beside the new one, both oriented in the same position. I did this because the new pigtail had two black wires and I wanted a reference of which wire was which, so that I did not wire the new plug on backwards.
The second picture shows the wire ends prepared for soldering. It isn't a very good picture but you can see that I've applied solder to the bare wire ends. I used a high quality silver electronics solder. Heat the end and let the wire soak up all the solder that it wants, so that there is an excess of solder on them.
Picture #3 shows the wires soldered together. Basically, hold to two wire ends side by side and touch them to the soldering iron until the solder melts and the two ends join. Once they are joined with solder, lift them away from the iron and let the solder solidify. This makes a continuous wire joint with no twisting of wires, etc. I was taught this procedure by an electrical engineer many, many years ago.
Of course, make sure you put the shrink tubing on the wires before you solder them and position it as far away from the join as possible while you're working on it. The plug kit that I bought included two pieces of very high quality shrink tubing that not only shrunk, but apparently contained some sort of sealant that melted. I could see it coming out of the ends of the joints.
Picture # 4 shows the wires wrapped with the ground strap. I unwrapped that later when I repaired the foil shield. You can see I twisted the wires. The wires in the loom were twisted originally, and I'm sure that was done on purpose.
Picture #5 is the repair of the aluminum foil shield. I got a some common household aluminum foil, cut a strip about an inch wide and 6 inches long, twisted it to the piece that was still attached and wrapped it around the wire. I then wrapped the ground wire around that and secured it with electrical tape. The tape used here is Scotch 700 Commercial Grade Vinyl Electrical tape. It's supposed to be good up to 176 degrees. It was about the best I could find at the auto parts store.
The last two parts of this are putting the wire back into the loom and wrapping it with new fabric tape.
The first part is getting it back into the loom. I ran my finger down the opening in the loom to hold it open and push the wires back in. You have to be careful not to tear the aluminum shield. Picture #1 below shows the finished result.
The last step is wrapping the loom tightly with fabric friction tape. I just learned about the existence of fabric friction tape. It is apparently used to prevent rubbing through the wiring looms. I got a roll at Ace hardware but it can be purchased online. The last picture here shows the final product, wrapped in two layers of the fabric friction tape.
Once I was done here, I routed the loom back behind the thermostat housing where it came, pulled it down into position and plugged it back in. I used a healthy dose of dielectric grease on the plug.
That diesel roaring to life was a sweet, sweet sound. I replaced the cold side CAC tube, the air intake pipes and the air filter and all is good. I will be doing some driving around here in Colorado locally (close enough for a AAA tow) before I head back home, but I suspect I have a good repair here.
I hope this information will be helpful to someone in the future. The way Ford expects you to fix this problem is to replace the engine wiring harness (about $750 just for the harness). This fix cost me about $40.00 for the pigtail kit and about 5 in high quality electrical and fabric friction tape.
i've been an electrician for a fair bit of time... the ONLY tape
i use is scotch 33+... it's around $4 a roll, but it lasts forever.
on short notice, the 700 will get the job done nicely, and when
it's all that is available, ya run whatcha got.... but a couple
rolls of 33+ for the toolbox wouldn't be a bad thing.....
seriously. about a year ago, i had to revisit some 480 volt
splices i'd done in a hospital, as an apprentice... the tape
looked as good as new, and could be unwrapped. that tape
has been on there 34 years.
friction tape is mainly for bulking up a splice or conductor,
in old school cable splicing. after the connection is secure,
you cover it with varnished cambric tape, for the dielectric
strength, half lapped friction tape, two layers, and scotch 33+,
two layers, again half lapped.
i've had splices done that way in underground vaults with 480
volt 3 phase circuits submerged in water for multiple years,
without shorting out.
Looks like a good repair David. Thanks for the great write-up and pics, not to mention the part #'s! Nice to have that info on FTE. Also, it's nice to hear there's folks out there willing to help like that.
The way Ford expects you to fix this problem is to replace the engine wiring harness (about $750 just for the harness). This fix cost me about $40.00 for the pigtail kit and about 5 in high quality electrical and fabric friction tape.
The reason for this, is because the CKP and CMP circuits are ground-shielded (as you already know by now). Therefore, overlaying or repairing those circuits is not a repair method Ford endorses. As far as the price for the harness, assuming yours is a late-build 2004 there are two different part numbers depending on the Navistar ID#. One is listed for $314.14 and the other is listed for $447.23 for tituswillfordparts.
At those prices you might even be able to get it even cheaper than that at Tousley Ford or partsguyed, since they both seem to be able to get parts at lower prices than even what I pay at my discount from my workplace.
I jsut wanted to thank you for posting this. My husband was in Florida and went to leave to come home over 1200 miles. The truck had just been in the shop over 1500 in cost to do the dummy plugs. Would not start when hot. Went out to start the truck and it just cranked. He did not have all his tools with him so had it towed to Ford Dealer in Port Richey FL. The dealer came back and said 2600 to fix the truck needs a camshaft position sensor and all new wiring harness becuase the pigtail to the CMP was broken. I started researching and found this posting about the WPT359 and called the dealer and asked that they order the part and replace the pigtale with this part. Initially the Ford dealer acted like I was crazy. They did it and we got it running for 500.00 still more than I care to spend but due to the fact that they wanted 2600.00 my husband was able to get home and it is all thanks to this information being available. Thank you again.
Years later this thread is still helpful.
We had an intermittent crank-no-start for nearly a year. We never saw a P2614 CMP error, so we wasted much effort in other areas.
Then I checked the cam sensor resistance at the PCM connector pins 31 & 43 and got 8 meg. When cranking the signal was there, but the resistance was way high.
Next weekend we go after this connector!