EEC Fuse and the MLP Sensor

[paul.milne]

I didn't take it as one, I doubt anyone else did either...

I was going to ask about the manual you posted the pictures from. Is there a way to get one of those? Sounds like something that is nice to have! I've also been thinking about other factory manuals for the vehicle, are there any good places to get those for the engine and such? If I'm going to keep this vehicle for the long haul, I can certainly see the benefit of having them.

 

[paul.milne]

I have another question I have to ask that I haven't gotten to yet. What else do I need to do while I have the pan off? I was going to replace the filter and see about flushing the transmission. What else? I have 160k miles on the vehicle; I've been thinking a new transmission was in order soon anyway, but what can I do to inspect it to determine its condition? Is there any other preventative maintenance that can be done to extend it's life?

 

[Glacier991]

Well certainly replacing the filter is one thing you can do. I would also add a plug to the pan. If you were averse to getting back in there I'd also replace the EPC solenoid, but that's up to you. It is expensive ($112). They do wear and wear out so it is something to consider. Have you read the 5r55E valve body rebuild diary? that's something you can do as well.

Main keys are clean fluid, cool fluid. Filters, external filters and coolers.

Band adjustment is not a bad idea either.

If you have the delayed reverse, adding the new double lip seal to the low/reverse servo while you are in there ain't a bad idea either.

(rambling here... long day, couple cold beers...so I'll stop....) no WAIT... the manual

FORD puts out awesome manuals on their transmissions. big 3 ring binders full of info. They cost a bunch but show up on E-bay often at a fraction of the price. I did a bunch of posts recently on them... I'll have to find that thread and PM it to ...you....Expect to pay $50 or so.

 

[paul.milne]

I did all my research on this site with the blown EEC fuse in mind, so there is probably a whole lot out there that I should be looking into wrt transmissions... guess I know what is in my immediate future...

I saw some comments on hot fluid an such, but I haven't run mine very hard. How does one know how hot the fluid is and at what temperature is it "bad"? Perhaps I should be searching and not asking the questions here. I guess there is a lot I have to learn about explorer transmissions.

I have no clue what delayed reverse is nor the comments proceeding it (except the reference to cold beer; that caught my attention!)

I'll look for manuals on ebay, see what I can find; thanks again for the info.

 

[Glacier991]

Well this one has kept me puzzled. Today, after considering what you found, I have come to another working hypothesis.

In neutral, park and 1st the only solenoid that is energized is the SSA. When it shifts to 2nd the SSA stays energized AND the SSC energizes.

Now if we assume you had some form of current leakage (thus far of unknown origins), drawing beaucoup current already, but in combination with ONE solenoid not 30 amps.... it could get pretty hot alright (melted insulation on the power wire) but might not trip until we add the current draw of the SECOND solenoid to the witches brew of current draw. That could explain why the SSC is ok.... might also explain why the other trannie tech suspected SSA.

Anyway, a thought.

ps. to Paul: I shipped the item we discussed. It's use should be intuitive, if not PM me.

 

[paul.milne]

Which solenoid is it that has the melted wires in the picture I posted? The second solenoid back on the left hand side of the transmission is the one, what is it called? Is that one SSA?

 

[Glacier991]

The side with two solenopids is home to SSA and SSC. SSA is the one cloest to the low/reverse solenoid (the big round cover plate).

 

[paul.milne]

Part replaced, filter changed, pan back on, fluid added, car started, shift into second gear... no blown EEC fuse! Looks like replacing the harness did it! We took her out for a drive; seems to all be well. I'll drive it to work tomorrow and see if she holds. I expect she will since she passed the real test which was the shift into second gear.

Here is one last picture of the offending piece. One problem that stumped me for a while was removing that little retaining clip off of the harness piece that sticks up out of the transmission. I pried and pulled and pushed for an hour... Then I was sitting there dripping with transmission fluid wondering how in the world it was going to come out of there. I looked in the box and out fell the little retaining clip in the middle of the picture below. Ah, but that wasn't the end of it. Since the transmission was in the car it appeared impossible to get the right leverage to pull that thing off. I needed some other tool, a screwdriver wouldn't do it. I couldn't get pliers on it... I wandered around the garage and the shed and finally I spotted the right tool to use... a paint can lid remover. Ok, maybe it wasn't the right tool, but it pulled that pin off lickity split!

If anyone is interested, here is approximately what it cost:
Two weeks and
$80 first diagnosis & second tow (insurance picked up the first one)
$75 second diagnosis (Ford dealtership)
$80 wrong part
$0 third & subsequent diagnoses (thanks to Glacier991 and this forum!)
$90 right part
$16 filter
$15 fluid
---------
$356

I didn't include all the driving back and forth between here and AL and the rental car since that was more related to circumstance rather than fixing the problem.

 

[Timoteo]

One thing I might add here (and to break up the longest running 2-man discussion, sorry) is soleniods can draw excessive current if stuck open. There is typical a high initial current that creates the magnetic field to draw in the spool or cylinder, as spool moves to its drawn in position the (holding) current is reduced. If the spool is stuck and doesn't move your left with the high current for an extended period which could overheat and melt the insulation on the wires (just like what your pictures show).
Just a thought, if it may help.

Tim

 

[paul.milne]

Do I need to replace the solenoid too? It's a little late for that with the pan back on and fluid in it, but I don't want to have any more trouble with it either. I could probably test it by putting it in second and driving for a while in second, but I'd hate to burn up another harness. It does seem to fit the condition under which it PROBABLY blew. I was driving up a steep hill hauling a boat, so it may be that it was in second for quite some time up that hill. I am really not sure what gear I was in at the time, but it could have been second... It also could have been in another gear and shifted into second as I was climbing the hill which caused the problem found in troubleshooting, that is shifting into second causes the EEC fuse to blow.

Is there a way, without dropping the pan and such to test if the solenoid is stuck open as you suggest? Would the resistance measurement still be good if the solenoid was stuck open? Would the solenoid slide in and out of the valve body easily if it was stuck open? Is the physical appearance of a stuck open solenoid different than a normal solenoid?

 

[Timoteo]

I can't say for certain that a solenoid was stuck, I'm giving you a suggestion to explain the over heated wires. If a solenoid was stuck it could have been due to debris or burn ATF, those issues are hopefully resolved now. It's possible that wear may have been a factor, which could still come into play. You can't do an electrical test, because you can't electrically test for mechanical wear or interference. I solenoid is just a whole lot of wire wound up into turns with an iron or steel cylinder in the middle. The intent is to move the iron to a more desirable place with those turns (typically against a spring), that more desirable place draws less current. If the iron doesn't move you draw higher than normal current for an extended time (over-heating). Most coils are rated to be continuous duty in the "desired position", so having it in second for an extend period wasn't by itself a problem.

Good Luck

 

[Glacier991]

I'd point out that theoretically, a solenoid stuck "on" or stuck "off" is supposed to, and usually will throw a code in this transmission.

 

[paul.milne]

It's been over a month and about three thousand miles later (took a trip to Texas this last weekend) and no more problems with the transmission and fuse blowing. Thought I'd post an update to say that replacing the wiring harness solved the problem. Couldn't have solved it on my own without this forum, thanks once again!

 

[Glacier991]

Great... thanks for the update.

 

[6scooter9]

I just started on here and i don't know if i am on the right spot or not, I posted a minute ago some where else. I think. But this Glacier991 seems to to know the hard stuff. But here is an easy one I hope. I just bought a 1993 Ford Explorer w/4.0 litre in it. The idle is at about 2700 to 3000, and i don't know how to adjust it. If anyone has some i would appreciate it very much. I will really have an opinion about these suv's if i can drive it down the road instead of it driving me.LOL.