Sadly, since my last post, this car has become a nightmare.

I bought the '07 (I confirmed an '07 with the VIN) and went 100 miles before cooking the tranny, which once pulled was determined to be a wrecker sourced dice roll.

I sent the trans to a reputable builder that I've been doing business with for 15 years, and it's still doing the same thing. Slipping in all gears. That is, it'll cruise at constant speed in any gear, but any sudden power input will rev the engine without a change in speed, and a bit of an unhappy sound from the trans.

My guy said that anything is possible - including their mistake, but I'd like to rule out the chassis first. The thought of trying to get the car 200 miles back to him and have him re&re only to find out that I've missed something...

I've pinned out the harness back to the ECU and am going to install LEDs with 1K resistors on each of the for solenoid lines to see if the ECU is sending signals to the trans.

Problem is, I can find no documentation on what the pressure control solenoid wire should be sending (besides pulse width modulation) - ie, is high duty cycle high line pressure? or when the converter lockup solenoid should be engaged. Even Ford says they have no such documentation.

I figure the converter will be continuous when applied? That is, for test purposes, just grounding the solenoid return for a few minutes while I play with throttle input at speed will be fine, but what about the pressure control? if it's not made for continuous duty, i don't want to burn it out.

Anyone else ever mucked about with testing in this manner?

 

You know what is not happening and are attempting to drain the ocean to determine why.

From what I gather from your earlier post the problem was present at the time you were driving the car home. At that point the trans could have been half cooked already before you took it. That said , suppose we consider a somewhat different approach?
Can you manage to get hold of a scan tool and check just what kind of codes could be in the vehicle's memory? Hopefully, from them you can get some direction. I can appreciate what you are attempting to do, but there is an easier way and that is with a good scan tool which will not only give you codes, but you will be able to energize and denergize solenoids through the tool.. This is usually only half of the check because it will only tell you the solenoid is energized,electrically but we don't know if it is actually working physically.. Sometimes you can rent a scan tool from some auto supply stores.
I would think a reputable trans shop would have the type scan tool needed.
You could be chasing a wild goose suspecting solenoids when there is a trans module to consider and the PCM (Powertrain Control Module).
This is why a code check might be able to help isolate the problem way before you unnecessarily spend a lot of time and $$.

 

Lol, i Like the way you phrased that.

I don't have a tool good enough to actuate outputs, but there are no DTC's stored.

in fact I am suspecting the ECM (PCM - same box up on the inn er fender) , but worry that I might have fried the new trans if it's running with low pressure.

As crude as it may sound, if i knew what the tranny wanted to see, I could rig up a quick emulation board and confirm that the internals are correctly functioning, then buy a new ECU if this should be the case.

In theory I could build a $10 "paddle box" to control the four output lines and run it as if it were a manual.

So far I have determined that all four solenoids, if not mechanically moving their armatures within the valve body, are electrically intact. I have a stethoscope here somewhere - when I hunt it down I should be able to hear them.

Incidentally, in the midst of all this - layed off after 23 years this week. So although i don't have a dime to spare, i do have some time.

Jim.

 

Well, some good news. Hammering away at everything that I can find, and assuming the internet is correct, I've figured out 3 of 4 lines - the best news being that an absence of the EPC signal, will result in high line pressure - no fried bands or clutches.

Got the binary sequence to gear selection.

Now only unclear if the converter lockup signal - also variable - is locked, or unlocked if absent.

Seems to me that a 5 minute test drive with 4th selected and the EPC at full pressure - and a quick switch (back and forth) between the TC solenoid ground to open while blipping the pedal and watching the tach, should definitively confirm bad internals, or bad external control.

 

A lot of us have after a number of years have been put out to pasture due to economic conditions or downsizing and we know where you are coming from.

With your experience , there is someone someplace hoping to find someone that will show up for work and actually care about working, we just have to find them.Been there.
If you want to go in the direction you explained, why not, go for it ! You might come up with something nobody has considered and invent/discover a new procedure. A good portion of some tests and procedures came up by accident more so than on purpose. If you would , let us know how you make out with this, thanks.

 

Before changing the PCM, be aware you will need to have the replacement PCM programmed to your vehicle before turning the key on.

This is why,
The replacement PCM will not be recognized by your vehicle and will refuse to start due to the anti-theft system. The kicker is, if you do attempt to start without programming the replacement PCM , now the vehicle gets confused and NOW will not start with the original PCM either. That will require a dealership tech with access to
"as built "info or a certified locksmith with access to that same info.

 

To be quite frank, my "problem" at the moment resembles why I was no longer of use.

20 years ago the manufacturer supplied schematics, waveforms testpoints, and test parameters. Now, not only do they expect you to simply replace the board, but will void the warranty if you don't. "Skilled trades" have all but gone to hell - glorified parts swapping monkeys that don't even know what the parts actually do.

Remember when there were television repairmen? Lol.

Meh, I taught myself to repair cameras by digging through a manufacturer's dumpster. Fist digital I ever owned was built from parts .

...

It's taken a bit of doing but I can confidently operate the tranny without the ECU. Although obviously the ECU will store DTC's and display the MIL and a yellow wrench on the dash.

It's Sunday, so a break with the other half and a few cold cups - not like I'm doing anything tomorrow. I learned how to make waffles from scratch this morning.

I felt that the reverse engineering and eventual solution might be "interesting" enough to add it as a page on my own site, so I'd be happy to link it here when I've written it and have the photos and diagrams done, but fair warning - my language can be a bit .. colorful.

...

Surprisingly (being rural), work appears quite plentiful here, despite the big strong twenty somethings wearing $200 headphones outside the beer store (in Toronto no less!) holding up signs to the contrary.

Perhaps less than prestigious - Auto glass installer, overhead door tech, but they're certainly out there.

Wife says I need a break - take a few months and work on my own projects, relax - and I thought this ideal! But to be honest, It's already hard to focus. I've just never not worked.

Coach and RV tech opening 45 minutes away. The ad sounds as if it were written for me, and I'll bet just the photos of the build of my own bus will get me that handshake.

Jim.

 

Oops, almost forgot. Thanks for the ECU mismatch info - was aware.

You'd be surprised (or perhaps not) at how many products - especially multi board - that you can no longer just slam in a test part.

The one I'm considering if it comes down to it ($249, correct Ford part number) requires the VIN when purchasing and comes with 2 uncut keys - although the existing should work).