sigmanf150

Oh boy, got into the truck yesterday, fired it up, and saw the check engine light come on and TRANS FAULT was on in the odometer section and the OD off icon was flashing.

I tried putting the truck in reverse and it took a good second to engage.

I have the Ford Rotunda VCM II code reader programmer so I'm going to hook it up and see what is up.

Those of you that have had this happen, what had the problem been? Solenoids/ sensors etc? Does this indicate catastrophic damage? I did not drive it when the warning light came on, so I'm hoping it is not severely damaged. The tranny looks like it may be the original that came with the truck in 2004 but i have 301,000 miles now so I'm hoping at some point it has been rebuilt. I have the 6.0 Powerstroke tranny cooler mod with a external spin on filter, and the fluid was just changed a few months ago. It's still Cherry red and not burnt looking or smelling.

I'll get out my VCM programmer and see what's up. If it just a solenoid or speed sensor, is it easy change? I don't have a lift, so I'll be doing this on the ground with ramps.

Thoughts??

supersky

I just had this issue. My truck was throwing P0748 and P0960 codes pointing to the electronic pressure control solenoid. Not sure what codes yours is throwing. I replaced it last weekend and it fixed the problem for about a week. It started throwing the same codes a couple of days ago so now I'm thinking of replacing that solenoid again, the shift solenoids, and the wiring harness they are connected to. If it only temporarily fixes it again, then I'll have to take it to a transmission shop to get a professional's opinion.

It shifts a little harder from 1-4, but shifts smoothly into overdrive which is why I'm also replacing the shift solenoids. Might as well while I've got the pan dropped.

I also had to do this while laying on the floor of my garage. Not too bad, but if you don't have a drain plug installed on the pan, it's going to take a while to drain the fluid. Just go slow and it won't be too bad. Once you drop the pan, you'll see the valve body, the black plastic wiring harness, the shift solenoids, and another solenoid (not sure what that one is called) attached to the valve body. You'll have to drop the valve body in order to get to the electronic pressure control solenoid. Make sure you take pictures so that you remember how everything is lined up before you start taking it apart. Saved me from huge headaches.

Here is what the solenoid looks like: http://www.rockauto.com/catalog/more...089&cc=1432394

You'll also have to take the transmission range sensor that's located on the outside of the transmission off in order to get the solenoid out. When you put everything back together, make sure you line it up correctly or else your truck might not start, or if it does start, it won't move. I learned that one the hard way, but was able to figure it out because of this:


Sorry for so much info, but just wanted to make sure you didn't have the same issues I did. Hopefully this helps.

sigmanf150

Wow! Thanks for the very detailed response!! Your post is extremely helpful! I will be hooking up my Ford VCM scanner this evening and hopeing it's something simple! Thanks for your help! I'm technically minded and have no problem tearing into the tranny to fix it. I just hope fixing it like this will be cheaper than just replacing the whole thing.

sigmanf150

Ok so I finally had a chance this evening to hook up the Ford IDS VCM II reader/programmer and discovered 5 codes related to the Trans Fault issue. Here are the codes that showed:


P0740 Torque Converter Clutch Control Circuit
P0743 Torque Converter Clutch Control Circuit- Lock Up Solenoid
P0755 Shift Solenoid B or Shift Solenoid Pressure Control B
P0758 Shift Solenoid B or Shift Solenoid Pressure Control B
P0962 Pressure Control Solenoid A or Line Pressure Control


All of these are registering electrical failures and stating there may be a short in the harness. The fact that all of them suggest there is an electrical short, Im going to start looking there first by checking the two plugs from the transmission harness into the PCM. Then Ill have to drop the pan(Thank goodness I installed a drain plug!)


Thoughts?

supersky

From those codes it would seem like the internal wiring harness is bad. Like you said, I would check the two plugs from the transmission harness into the PCM first, then open it up. I just ordered mine from Amazon last night and it was $32.95 for a refurbished one.

Here's the link:

sigmanf150

I found the electrical black plastic internal harness on eBay for $38.88 and a solenoid kit with new filter and gasket for $87.88.

Should I replace the solenoids while I'm in there? Again I do not know the age of the transmission or if it's ever been rebuilt. I did service it shortly after buying it and the fluid was pretty gross.

Thoughts?

supersky

That's what I'm doing. I've decided to replace all the solenoids and the wiring harness at once. I ordered the solenoids from rockauto.com and the wiring harness from amazon.com. I spent $120 total. Fairly cheap considering when I priced just the electronic control solenoid at AutoZone, it was $80. Rockauto has it for $35.79.

Mary B

I am wondering what the final verdict was and did the solenoids and wiring harness fix the issue?
I went out to get in my truck on saturday and once I turned on the truck the Trans Fault was on with the check engine like and the O/D flashing light. I had just driven it on friday with no problems what so ever. The transmission fluid was changed a few months ago and it looks great. I have called the service department at my local Ford dealer and they say they've never seen this before. I called another mechanic friend and he said it sounds electronic.
I'm at a loss and concerned because I know there have been alot of issues with these particular transmissons.
Help Please!!!

Mod (Ret.)

I'm interested in the "powerstroke 6.0 trans cooler/filter" mod that your truck has. Can you provide more info on this?

supersky

Mary,

Sorry I never updated the post after I did all the work. That's exactly what happened to my truck. I had just come off a long trip from Arizona to Chicago and back with no issues the entire way. Shortly after returning is when I started having issues. After I replaced everything, the issue was resolved and has not returned. My guess is the wiring harness was causing my solenoid to fail, but instead of replacing just the wiring harness and electronic control solenoid, I replaced the rest of the solenoids, too. I have also gone on multiple trips since then and you can't tell that anything ever happened. I hope this helps.