4R55E ss2 solenoid fault P0756 but solenoid tested ok

[Tomkw51]

My 96 explorer with 4r55e has a shift issue. It had the p0756 error. Most of the time it doesn't want to shift into 2nd unless I let up on the throttle. If I get to about 30 mph stop hard acceleration the rpm goes up without changing speed.
I first replaced the ss2 solenoid, replaced the filter and fluid, but no change. Then I installed a remanufactured valve body with the bonded gasket and all new solenoids, but still no change. I verified that the ECU was operating the ss2 circuit and checked the solenoid operation by manually grounding it. And could hear it operating (while under the vehicle).
I am at a loss as to the next step. I am considering trying to adjust the intermediate band. Is there anything else to check, either before or after after. if the adjustment fails?
Any suggestions will be appreciated!

 

[rasouth]

This may be a silly question but did you try to clear the code afterwards?

 

[Tomkw51]

This may be a silly question but did you try to clear the code afterwards?

Yes, it just comes back on. Thanks

 

[German Engineer]

Maybe check the wiring and the connections, especially the connector from the wiring harness for the transmission, if you haven't:

2nd gen issues? Try this first! | Ford Explorer - Ford Ranger Forums - Serious Explorations (explorerforum.com)

 

[Tomkw51]

Thank you for your reply. I sorry for not make my explanation clear (made too many unconscious assumptions) The solenoids are always wired hot. When bypassing the ECU with the ignition on (but not running) and manually grounding the ss2 solenoid, it actuated. I Could verify it was working because it was audible through the casing. I also drove the vehicle with a spare solenoid inside where I connected a hot lead to the solenoid contact and the the other contact to the wire on the ECM (pin 1) contact for the ss2 solenoid. Thus my spare solenoid operated at the same time as the one in the transmission. The ECU was operating the it by grounding circuit 315 and the wire I had spliced into it. Thus the fault can not be with the wiring , ECU or valve body.
My speculation is the intermediate band, or a pressure regulating component outside of the valve body is not working properly. I was hoping to fix it without removing the tranny from the vehicle. This is looking less and less likely.
I am hitting the limits of my troubleshooting tools and knowledge. Unless someone can suggest a fix that can be done in place almost ready to start to looking for used transmission that is functional or something to rebuild.

Maybe check the wiring and the connections, especially the connector from the wiring harness for the transmission, if you haven't:

2nd gen issues? Try this first! | Ford Explorer - Ford Ranger Forums - Serious Explorations (explorerforum.com)

 

[German Engineer]

I suppose the best advice that I can still give you right now is to google for: "1996-2001 Ford Explorer workshop manual", if you don't have that manual already.

It literally has sections with hundreds of pages full of instructions how exactly to diagnose and fix each problem for each type of transmission.

I'm sorry, but I just don't have the time to go through 5000 pages to find the right section for your transmission in there.
But I'm pretty sure you'll find some great advice and a very detailed and illustrated step by step instruction or even a chart for diagnosing and fixing your problem in there, if you're willing to do the reading.

 

[Tomkw51]

I suppose the best advice that I can still give you right now is to google for: "1996-2001 Ford Explorer workshop manual", if you don't have that manual already.

It literally has sections with hundreds of pages full of instructions how exactly to diagnose and fix each problem for each type of transmission.

I'm sorry, but I just don't have the time to go through 5000 pages to find the right section for your transmission in there.
But I'm pretty sure you'll find some great advice and a very detailed and illustrated step by step instruction or even a chart for diagnosing and fixing your problem in there, if you're willing to do the reading.

 

[Tomkw51]

Thank you, I really appreciate all the help I can get. I'll Will certainly try to get my hands on that manual. I do have the ATSG manual, but as you can see I've been improvising, since I don't have the specialized tools or knowledge for such diagnostics.
I'm learning far more than I have any desire to know. Nothing like necessity to expand one's abilities.

 

[German Engineer]

Thank you, I really appreciate all the help I can get. I'll Will certainly try to get my hands on that manual. I do have the ATSG manual, but as you can see I've been improvising, since I don't have the specialized tools or knowledge for such diagnostics.
I'm learning far more than I have any desire to know. Nothing like necessity to expand one's abilities.

It's surprisingly easy and affordable to find online from numerous legal or illegal sources.
Of course you'll need to improvise, but then again, some of the more specialized tools may even be available for rent at one of your local auto parts chain stores as well.

Good luck, that manual is quite a treasure trove for all sorts of repairs, hope it helps.

 

[96eb96]

My 96 explorer with 4r55e has a shift issue. It had the p0756 error. Most of the time it doesn't want to shift into 2nd unless I let up on the throttle. If I get to about 30 mph stop hard acceleration the rpm goes up without changing speed.
I first replaced the ss2 solenoid, replaced the filter and fluid, but no change. Then I installed a remanufactured valve body with the bonded gasket and all new solenoids, but still no change. I verified that the ECU was operating the ss2 circuit and checked the solenoid operation by manually grounding it. And could hear it operating (while under the vehicle).
I am at a loss as to the next step. I am considering trying to adjust the intermediate band. Is there anything else to check, either before or after after. if the adjustment fails?
Any suggestions will be appreciated!

Could be a broken band or tired servo.