1996 Ford Explorer Transmission Shift Solenoid Issues

[Red_Lion]

Sure I believe that to be more of a realistic failure rather than a electrical fault. I believe your next step is in that direction, servos, valve body, bands.

Is this what I am looking for:

http://www.google.com/imgres?safe=o...bnh=177&tbnw=146&start=16&ndsp=26&tx=46&ty=83

and that is what I should remove and check out? It says something about throwing away lock nuts and screws, do I need to pick that up before I do this?

 

[JK080]

Yes that is the servo, there are two. There are many places the problem could be, you would want to try the easiest places first and the servos are not too hard to get to.

Don't worry about the lock nuts at this point, lets find the problem first. They say to replace them because there is a seal on them, you may not need to deal with them anyway if the servo comes out without to much trouble.

 

[Red_Lion]

Yes that is the servo, there are two. There are many places the problem could be, you would want to try the easiest places first and the servos are not too hard to get to.

Don't worry about the lock nuts at this point, lets find the problem first. They say to replace them because there is a seal on them, you may not need to deal with them anyway if the servo comes out without to much trouble.

Are the lock nuts easy to buy? This may be an incredibly stupid question, but do I drain the tranny fluid first? Also, I am working on the left servo or both?

FYI, Explorer drove decent today, error code P0761 popped up again, but even the RPM's were lower than before. Hopefully I can get the servo off and check them out.

EDIT: Do I need that Servo Cover Compressor to take off the servo(s) or is there another way to take it off, I read in that other post that you spray a lot of oWD40 or Gumout to loosen and try to get the OD band adjusting nut loose, but I haven't a clue of what that is at all.

 

[imp]

Are the lock nuts easy to buy? This may be an incredibly stupid question, but do I drain the tranny fluid first? Also, I am working on the left servo or both?

FYI, Explorer drove decent today, error code P0761 popped up again, but even the RPM's were lower than before. Hopefully I can get the servo off and check them out.

EDIT: Do I need that Servo Cover Compressor to take off the servo(s) or is there another way to take it off, I read in that other post that you spray a lot of oWD40 or Gumout to loosen and try to get the OD band adjusting nut loose, but I haven't a clue of what that is at all.

Then you need to proceed with utmost care and caution, if at all. imp

 

[Red_Lion]

Then you need to proceed with utmost care and caution, if at all. imp

Of course, since I have not worked on that part of a transmission before. This is why I am asking these questions to make sure I proceed with utmost care and caution. Perhaps you could answer some of the questions I posted, that would help with the care and caution part.

 

[imp]

Of course, since I have not worked on that part of a transmission before. This is why I am asking these questions to make sure I proceed with utmost care and caution. Perhaps you could answer some of the questions I posted, that would help with the care and caution part.

Guy, I'm having some kind of problem with the forum. I got your first message, now can't go back to look at it, or others. No option that I can find, control panel, nothing, will do it. Maybe use PMs instead.

Now, having found this post, which is what I saw in the notifications, now gone: Sorry I was a little short with you. Usually, "don't have a clue" means individual is at a loss; no matter what I can say, won't instill the experience and probable technical ability needed. Now, let's look at the original problem, give me a bit of time:

I have a Transmission Solenoid problem. First, I was getting an error code of P0751 for Solenoid SS1/A. I replaced the whole harness and Solenoid A and car worked for a little while. Did it work AT ALL, before solenoid replacement?

My check engine light came on again and I did another diagnostic and received a code P0761, which is the SS3 solenoid or Solenoid "C". When I got home, I did another diagnostic on now received a 2nd error code of P0751, Solenoid SS1 or Solenoid A. So, now I am a little confused. Can One solenoid affect the other? No. But solenoid malfunctions can confuse the PCM, and then codes get thrown which are misleading.
Could Solenoid C have gone bad and then affect Solenoid A or vice versa? Extremely unlikely.

I never previously had a Solenoid C issue, only A, now I have them both after a full harness install.

Both Solenoid C and A are replaced, but received same error codes again when driving about 400 miles, first P0761, then P0751. I thought maybe it was the PCM, so I replaced the PCM, and it worked for awhile, then bam, I am getting the same errors, so I do not think it is a PCM issue. Does it always work for awhile after attempts to remedy?

I do not think it is the PCM Power Relay, but I could be wrong. Power relay failure kills everything.

I know I can test the voltage on the Solenoids, to see if they really are bad, correct? No. Presence of VOLTAGE at a solenoid, or any other "output device" of the PCM, tells you NOTHING about the condition of the device, save for that it is not shorted to ground.

Or is there something else that I may be missing, connection from the harness to the PCM perhaps or something else? I checked all fuses, great, all relays work, but I never did test them, just visual. HTH can you tell if relays are "working" by looking at them? Can you tell if their contacts are properly opening and closing, delivering power to the devices they control?

Is there something I can do to do further testing? Anyone know if I am missing some steps here or looking in the wrong direction?

You did not indicate in the start of the thread, exactly WHAT was the transmission doing, or not doing. Expecting to solve as complex an issue(s) as might exist here, by just viewing codes is like pissing against the wind.

I know I haven't helped, but then I'm not alone, right? What was the original problem(s) that led to all this? imp

 

[Red_Lion]

Guy, I'm having some kind of problem with the forum. I got your first message, now can't go back to look at it, or others. No option that I can find, control panel, nothing, will do it. Maybe use PMs instead.

Now, having found this post, which is what I saw in the notifications, now gone: Sorry I was a little short with you. Usually, "don't have a clue" means individual is at a loss; no matter what I can say, won't instill the experience and probable technical ability needed. Now, let's look at the original problem, give me a bit of time:

I have a Transmission Solenoid problem. First, I was getting an error code of P0751 for Solenoid SS1/A. I replaced the whole harness and Solenoid A and car worked for a little while. Did it work AT ALL, before solenoid replacement? Yes, it worked before the solenoid replacement, just not well, like now.

My check engine light came on again and I did another diagnostic and received a code P0761, which is the SS3 solenoid or Solenoid "C". When I got home, I did another diagnostic on now received a 2nd error code of P0751, Solenoid SS1 or Solenoid A. So, now I am a little confused. Can One solenoid affect the other? No. But solenoid malfunctions can confuse the PCM, and then codes get thrown which are misleading.
Could Solenoid C have gone bad and then affect Solenoid A or vice versa? Extremely unlikely.

I never previously had a Solenoid C issue, only A, now I have them both after a full harness install.

Both Solenoid C and A are replaced, but received same error codes again when driving about 400 miles, first P0761, then P0751. I thought maybe it was the PCM, so I replaced the PCM, and it worked for awhile, then bam, I am getting the same errors, so I do not think it is a PCM issue. Does it always work for awhile after attempts to remedy? It always works after I switch the PCM's, then it goes downhill and then I get error codes

I do not think it is the PCM Power Relay, but I could be wrong. Power relay failure kills everything.

I know I can test the voltage on the Solenoids, to see if they really are bad, correct? No. Presence of VOLTAGE at a solenoid, or any other "output device" of the PCM, tells you NOTHING about the condition of the device, save for that it is not shorted to ground. I am not understanding, JK080 and a others on here have stated that I can check through the PCM and the PCM Power Relay the Solenoid to see if it works or outputs the correct ohms, I have seen others do this test. You are saying the test is invalid and tells nothing of the solenoid and if it working or not?

Or is there something else that I may be missing, connection from the harness to the PCM perhaps or something else? I checked all fuses, great, all relays work, but I never did test them, just visual. HTH can you tell if relays are "working" by looking at them? Can you tell if their contacts are properly opening and closing, delivering power to the devices they control? Yes, I visually checked the harness for any issues with broken connections, bent wires rusted or corroded connectors, partially broken wires or loose wires. I am not sure why a visual check is not warranted.

Is there something I can do to do further testing? Anyone know if I am missing some steps here or looking in the wrong direction?

You did not indicate in the start of the thread, exactly WHAT was the transmission doing, or not doing. Expecting to solve as complex an issue(s) as might exist here, by just viewing codes is like pissing against the wind.

I know I haven't helped, but then I'm not alone, right? What was the original problem(s) that led to all this? imp

I am not sure if you read through the original thread, but I posted this in one of my responses to JK080:

The Tranny doesn't slip, but it can shift hard (because it is the shifting solenoid not working correctly) and it will RPM in the 3k's when going 65-80 MPH (after 80 it is smother, but when going between 65-80, it runs rough.) and will clunk when I stop once in awhile. The Transmission has been rebuilt, but it is not the tranny, as I have had numerous mechanics look at it and they say it is an electrical issue, which is what I am trying to pinpoint to no avail. Also, I have not really had any flares, it does, when the solenoid does the check engine not have power when going from stop to 2nd gear, but once I reset the PCM, that goes away.

When I last spoke to JK080, I was hoping he could give me a little more direction in how to take off the covers to the Overdrive Servo's and the like as it seems to need a special tool which I can barely find on ebay. Also, I have to remove part of the exhaust to get to it, which is not an issue, if I felt comfortable in taking off the Overdrive Servo cover and working on the components inside.

 

[imp]

Guy, I'm having some kind of problem with the forum. I got your first message, now can't go back to look at it, or others. No option that I can find, control panel, nothing, will do it. Maybe use PMs instead.

Now, having found this post, which is what I saw in the notifications, now gone: Sorry I was a little short with you. Usually, "don't have a clue" means individual is at a loss; no matter what I can say, won't instill the experience and probable technical ability needed. Now, let's look at the original problem, give me a bit of time:

I have a Transmission Solenoid problem. First, I was getting an error code of P0751 for Solenoid SS1/A. I replaced the whole harness and Solenoid A and car worked for a little while. Did it work AT ALL, before solenoid replacement? Yes, it worked before the solenoid replacement, just not well, like now.

My check engine light came on again and I did another diagnostic and received a code P0761, which is the SS3 solenoid or Solenoid "C". When I got home, I did another diagnostic on now received a 2nd error code of P0751, Solenoid SS1 or Solenoid A. So, now I am a little confused. Can One solenoid affect the other? No. But solenoid malfunctions can confuse the PCM, and then codes get thrown which are misleading.
Could Solenoid C have gone bad and then affect Solenoid A or vice versa? Extremely unlikely.

I never previously had a Solenoid C issue, only A, now I have them both after a full harness install.

Both Solenoid C and A are replaced, but received same error codes again when driving about 400 miles, first P0761, then P0751. I thought maybe it was the PCM, so I replaced the PCM, and it worked for awhile, then bam, I am getting the same errors, so I do not think it is a PCM issue. Does it always work for awhile after attempts to remedy? It always works after I switch the PCM's, then it goes downhill and then I get error codes

I do not think it is the PCM Power Relay, but I could be wrong. Power relay failure kills everything.

I know I can test the voltage on the Solenoids, to see if they really are bad, correct? No. Presence of VOLTAGE at a solenoid, or any other "output device" of the PCM, tells you NOTHING about the condition of the device, save for that it is not shorted to ground. I am not understanding, JK080 and a others on here have stated that I can check through the PCM and the PCM Power Relay the Solenoid to see if it works or outputs the correct ohms, I have seen others do this test. You are saying the test is invalid and tells nothing of the solenoid and if it working or not?

Or is there something else that I may be missing, connection from the harness to the PCM perhaps or something else? I checked all fuses, great, all relays work, but I never did test them, just visual. HTH can you tell if relays are "working" by looking at them? Can you tell if their contacts are properly opening and closing, delivering power to the devices they control? Yes, I visually checked the harness for any issues with broken connections, bent wires rusted or corroded connectors, partially broken wires or loose wires. I am not sure why a visual check is not warranted.

Is there something I can do to do further testing? Anyone know if I am missing some steps here or looking in the wrong direction?

You did not indicate in the start of the thread, exactly WHAT was the transmission doing, or not doing. Expecting to solve as complex an issue(s) as might exist here, by just viewing codes is like pissing against the wind.

I know I haven't helped, but then I'm not alone, right? What was the original problem(s) that led to all this? imp

I am not sure if you read through the original thread, but I posted this in one of my responses to JK080:



When I last spoke to JK080, I was hoping he could give me a little more direction in how to take off the covers to the Overdrive Servo's and the like as it seems to need a special tool which I can barely find on ebay. Also, I have to remove part of the exhaust to get to it, which is not an issue, if I felt comfortable in taking off the Overdrive Servo cover and working on the components inside.

Up front, I have not had occasion to open up any of the servos in these new transmissions. I got all "learning" on Borg-Warner transmissions designed and used many years ago. BUT, if what you're facing is similar to those oldies, you will find a stamped metal cover having a slot halfway across it's face through which protrudes an "arm" which pivots on a pin in the casting adjacent to the servo. This arm is acted upon by the PISTON within the servo. It PUSHES the curved arm outward, rotating about the pivot. The OTHER end of the arm has the appropriate shape, slot, groove, if you will, to accept a "key" which in turn presses against one end of a BAND, the other end of the band being held against the transmission case.

Thus, the SERVO PISTON moves the arm,. which causes the BAND to squeeze tightly around a DRUM, the drum being a part of a planetary gear system. Thus, the SERVO causes the BAND to APPLY, as the jargon goes. The servo piston has seals, usually O-rings, which can embrittle and crack, thus making servo piston movement sluggish. Or, the piston may BREAK. Any of various mechanical failures.

Regarding testing solenoids: Coil Resistance: you disconnect the solenoid from the harness, and MEASURE it's coil resistance, at the same time checking coil connections to ground. The former measures the coil's resistance, looking for a BURNED_OUT coil; the latter checks for a short circuit path to ground, which would render the sol. inoperative. If solenoid resistances are OK: then one must determine whether they are being ENERGIZED by the PCM. Having no access to the sophisticated test equipment which can do this, one can run the vehicle up on jack stands while observing signals applied by the PCM to the solenoids, using a voltmeter.

Bear in mind, that solenoids can FAIL mechanically, as well as electrically. They have a PLUNGER which rides in bushings, and pushes against hydraulic control spool valves, which then bring about the appropriate actions: shifts, TCC operation, initial engagement (like "N" to "D"), etc. So, if solenoids check out OK electrically, and the DTC code indicates solenoid failure, then we look at their mechanical condition, and if bad, replace them. imp

 

[Red_Lion]

Up front, I have not had occasion to open up any of the servos in these new transmissions. I got all "learning" on Borg-Warner transmissions designed and used many years ago. BUT, if what you're facing is similar to those oldies, you will find a stamped metal cover having a slot halfway across it's face through which protrudes an "arm" which pivots on a pin in the casting adjacent to the servo. This arm is acted upon by the PISTON within the servo. It PUSHES the curved arm outward, rotating about the pivot. The OTHER end of the arm has the appropriate shape, slot, groove, if you will, to accept a "key" which in turn presses against one end of a BAND, the other end of the band being held against the transmission case. This is the Overdrive Servo, it has an overdrive cover and seal, is this what you are describing? I do not see an arm, unless I am not understanding you correctly.

http://imageshack.us/photo/my-images/594/stkusenfiled15770agifge.gif/

I saw a tool used to take it off, but this person says to do it like this with no tools:

Same code, same car I experienced. '96 Exp Sport; P0761; no OD. I replaced the SS3, with no change. But I licked it. The code shows up when, after activating SS3, the PCM does not detect the reduction in RPM's associated with proper function. So, a mechanical cause can be the culprit. How to fix? Move the heat shield away from the OD servo port. Take the circle clip out of the servo port hole. This can be hard because the catalytic/exhaust is in the way, you only have about 1.5 inches to work with. Spray liberally with WD40 or gumout. The servo cover will probably be gunked in there because the cause of the problem is heat. Take the OD band adjusting nut and adjuster out. Take the nut off the adjuster. Put the adjuster back in and tighten it until the servo cover pops out enough for you to grab and twist it out. Take out the servo piston and spring. Eureka! The piston's rubber lips are hard as granite and razor sharp, causing the piston to stick in the servo cylinder most or all the time. So: either replace the piston, or, do what I did: take a 200 grit sandpaper and smooth the sharp edges all around, only about .2 mm, enough to make it dull (not sharp) on both bearing edges. Check the bore surfaces for crud, cleaning them with fine steel wool if necessary. Put it back together but first take out the band adjuster. Reinstall the spring and piston and cover and clip. Install the adjuster all the way, then back it off 1.25 turns. Install the jam nut. Reset the shield. You just saved a $1200 rebuild.

Thus, the SERVO PISTON moves the arm,. which causes the BAND to squeeze tightly around a DRUM, the drum being a part of a planetary gear system. Thus, the SERVO causes the BAND to APPLY, as the jargon goes. The servo piston has seals, usually O-rings, which can embrittle and crack, thus making servo piston movement sluggish. Or, the piston may BREAK. Any of various mechanical failures.

Regarding testing solenoids: Coil Resistance: you disconnect the solenoid from the harness, and MEASURE it's coil resistance, at the same time checking coil connections to ground. The former measures the coil's resistance, looking for a BURNED_OUT coil; the latter checks for a short circuit path to ground, which would render the sol. inoperative. If solenoid resistances are OK: then one must determine whether they are being ENERGIZED by the PCM. Having no access to the sophisticated test equipment which can do this, one can run the vehicle up on jack stands while observing signals applied by the PCM to the solenoids, using a voltmeter.

Bear in mind, that solenoids can FAIL mechanically, as well as electrically. They have a PLUNGER which rides in bushings, and pushes against hydraulic control spool valves, which then bring about the appropriate actions: shifts, TCC operation, initial engagement (like "N" to "D"), etc. So, if solenoids check out OK electrically, and the DTC code indicates solenoid failure, then we look at their mechanical condition, and if bad, replace them. imp

This is interesting, how do I test to see if it failed mechanically? So even though they work electrically, they can fail mechanically regardless. Is there a way to take them out and power them up to see if they work? Or do I try to blow compressed air through them?


Also, just to give you an update, yesterday the Explorer ran decent, I noticed when on an incline there was no issue in speed at all, the RPM's were still high, but it ran smooth when hitting 60-80mph. Usually, there is a clunk at braking, or really high RPM's and rough driving when hitting 60-80mph, but yesterday it was fine. Usually, if I disconnect the harness, reset or change the PCM and reinstall everything car runs great for a few miles, but then it just starts all up again.

 

[imp]

My error in describing the old servo appearance and operation. The pic posted shows that the piston drives directly against band linkage, not through an intermediate arm, as I described.

At any rate, if not familiar with the exact appearance of the device to be encountered, if one understands the concepts involved, i.e., a piston causes a band to squeeze and grip a drum, one can figure out whether anything is seriously amiss: broken, bent, etc. imp

 

[Red_Lion]

Can anyone help me with the Overdrive Servo and how to take it out and such? I cannot find out how to take this out, not in the Ford manuals or online. Just need a great informative instruction manuals or steps to follow. I appreciate all who have helped thus far, definitely useful for me.

 

[Red_Lion]

Bump

 

[imp]

see post # 7


http://www.explorerforum.com/forums/showthread.php?t=262491&

 

[Red_Lion]

see post # 7


http://www.explorerforum.com/forums/showthread.php?t=262491&

Thanks for the link, but I have seen that thread. It has great pics, but it doesn't explain how to take off the Overdrive Servo, I know he says he oils it until he gets it out, but that doesn't help me as I do not know what to oil and do. I just need the procedure on how to take that out.

 

[imp]

Thanks for the link, but I have seen that thread. It has great pics, but it doesn't explain how to take off the Overdrive Servo, I know he says he oils it until he gets it out, but that doesn't help me as I do not know what to oil and do. I just need the procedure on how to take that out.

I know. I will dig deeper after a bit of sleep, and try to give more concrete info tomorrow morning. Sorry for the delay. We all gotta sleep. iomp

 

[Red_Lion]

I know. I will dig deeper after a bit of sleep, and try to give more concrete info tomorrow morning. Sorry for the delay. We all gotta sleep. iomp

Thanks, Imp, I appreciate it. Sleep is definitely needed, for sure! Thanks again!

 

[Red_Lion]

Bump

 

[Red_Lion]

SO I am trying to do more research, and I cam across this: http://www.explorerforum.com/forums/showthread.php?p=3215517

This is the exact same problem I am having at this moment. They didn't receive any answers, but hopefully someone in the SUV forum can and point me in the right direction. I have been working on this for months now.

 

[JK080]

I ran across some info about a valve in the valve body being mispositioned can cause a p0761 code. In a 4R55E the symptom is no 4th gear and code p0761, in a 5R55E there is no 2nd or 5th gear but it didn't say if it set the code in the 5R55E.

Just something else to think about, however this is something that can only happen if someone assembles it incorrectly.

This is the only mention of a code p0761 in my entire database...

 

[Red_Lion]

I ran across some info about a valve in the valve body being mispositioned can cause a p0761 code. In a 4R55E the symptom is no 4th gear and code p0761, in a 5R55E there is no 2nd or 5th gear but it didn't say if it set the code in the 5R55E.

Just something else to think about, however this is something that can only happen if someone assembles it incorrectly.

This is the only mention of a code p0761 in my entire database...

For p0761 it says a gear problem? Not a Solenoid problem? In the code database, it says solenoid C(3) issue. it goes into 4th gear, but it does not go into overdrive after that. Should I take it back to the transmission person and tell them? Because this is the same issue I had before and after Tranny rebuilds. In other threads I have been shown or found, the issues that match mine seem to be some thing wrong with electrical or need to adjust the OD band on outside of tranny, is that something that is also a possibility? Should I look into that? Also, another person who had same issue took out OD servo on opposite side of the OD band adjustment and cleaned it. I have already replaced the solenoid and want to knows if the band adjustment or servo cleaning is a direction to go as well. Thanks for the reply, it is appreciated.