**SOLVED** 5R55E No/Weak Reverse, 1st Engine Braking Works

[Dirtman]

The computer can see the solenoids open or closed by monitoring the voltage across the circuit. If the solenoid fails to activate when commanded the voltage would not change and you would get a open circuit code for that solenoid. If the solenoid grounds itself internally the voltage would drop too much and you would get a short circuit code.

Computers is smart.

 

[Clayton]

Computers is smart.

haha, indeed, pretty cool how much you can do with relatively simple circuits.

Ok, so solenoids are doing their thing in reverse, anything else we can glean from PIDs? Is it time to pull the valve body and see what we see?

 

[Orca]

I went ahead and decided to not be a cheap ass and ordered a OBDLink MX.

Good choice. Coupled with good software (like FORScan), that should serve you well both now and into the future.

Here are all the PID's I found that were transmission related and cycled through the gears.

I'd suggest that you add PID "CCS" (Coast Clutch Solenoid).

What should we make of the transmission range switch voltage being maxed out and reading "error"?

That is rather odd. I wonder what you'd see if you monitored just that one PID (TR-V). Also, curiously, FORScan 2.3.33-beta for Windows doesn't offer such a PID for my 2004 Ranger, but that PID (Mode $22, PID $1151) is supported by my truck -- it changes between only 2 values (1.62V and 0.00V) as I cycle the gear selector through all the positions, which is exactly what I'd expect, per the ATSG 5R55E transmission manual.

 

[Clayton]

CCS remains at 0% through the gears except when in Man2, and then it goes to 100%

Ok, so TR voltage is def acting funny. I went ahead and loaded just it. Same readings, but I hadn't noticed before, where it says "Error" in all other gears, in Manual 1 it says 2, and in OD it says P.

 

[Clayton]

Oh, interesting, just looked up CCS in the Altra manual, and it says it should be off in all positions** except Reverse. Maybe we're getting somewhere?

**Edit: Should be on in Reverse, Man2 and Low

Edit2: Played with it a bit more and now I'm getting a 2-5 second delay and then CCS goes on when shifting into Low. No luck in Reverse.

 

[Orca]

CCS remains at 0% through the gears except when in Man2, and then it goes to 100%

So -- true or false -- CCS is reporting (via FORScan) as expected (per your chart) but not when the gearshift is in "1" ("Man1" / "Low"), assuming you tested that gear selector position?

EDIT: Scratch the above -- you keep editing your old post!

Ok, so TR voltage is def acting funny. I went ahead and loaded just it. Same readings, but I hadn't noticed before, where it says "Error" in all other gears, in Manual 1 it says 2, and in OD it says P.

How did you select/enable that "Transmission Range, Voltage" PID in FORScan Lite? I've never used FORScan Lite -- is it possible that you may be asking it to display a valid PID but in a bogus format (volts)?

When I use FORScan for Windows to query the PID called "TR3_V", it's querying a PID that Ford calls "TR-V". So I think there may be a bug in FORScan. In short, I wouldn't spend too much time focusing on the results of the "Transmission Range, Voltage" PID in FORScan Lite. But the "TR3_V" PID should be something to believe, AFAICT. In fact, its behavior in your 6 FORScan screenshots matches what one would expect for "TR-V", again per the ATSG manual.

 

[Clayton]

Sorry for the confusion, I edited the above post probably while you were typing.

Edit2: Played with it a bit more and now I'm getting a 2-5 second delay and then CCS goes on when shifting into Low. No luck in Reverse.

The PID details for TR_V is identical to TR. Available types are the various shift positions and there's no mention of voltage. It would seem to be a combination that shows voltage and shift position, but is not functioning properly for whatever reason. So, yeah, as you said, seems like we can set it aside.

 

[Orca]

Sorry for the confusion, I edited the above post probably while you were typing.

No problem. That's exactly what happened. I caught your 1st edit but almost missed the 2nd one.

The PID details for TR_V is identical to TR. Available types are the various shift positions and there's no mention of voltage. It would seem to be a combination that shows voltage and shift position, but is not functioning properly for whatever reason. So, yeah, as you said, seems like we can set it aside.

I suspect that @G8orFord might be able to clear up the FORScan Lite PID confusion for us.

Keep posting your testing results here. If I see anything that conflicts with the transmission data I've observed on my 2004 automatic 4.0L Ranger, I'll be sure to let you know. Good luck!

 

[Clayton]

Will do, and thanks for all your help-- having a place like this, with people willing to help out, changes stuff like this from being a frustrating game of throwing parts at the problem to a sometimes frustrating but ultimately enlightening learning experience.

 

[Orca]

I forgot to mention this... At some point, if you haven't already considered this, you might also want to add FORScan PIDs "EPC" and/or "EPCV" (Electronic Pressure Control, in PSI and/or volts) and "CPP/NDS" or "CPP/PNP" ("Clutch Pedal Position Switch / Neutral Switch Circuit"). IIUC, those would report the line pressure (EDIT: see next post) and the "neutral safety switch" -- information that was referred to earlier in the thread. I don't know why there are 2 "CPP/*" PIDs -- they may report the same thing. I'll have to look into that when I get a chance.

I don't have data from FORScan, but on my 2004 Ranger, I've seen EPC reporting about 55 psi with the engine idling in 'Park' at 1020 rpm and the EPCV is about 0.18 volts at the same time. I will try to check that under FORScan soon.

 

[Orca]

As I said earlier, I'm no transmission expert. Based on reading various sources since my last post, it seems that "line pressure" values are always higher than the pressure values reported by the "EPC" PID, so my reference to "line pressure" in the previous post is undoubtedly wrong. Sorry for any confusion.

 

[Clayton]

Good tip-- I'll check those in the morning. After that, I think I'm going to dig in. Here's my thinking: The band passed the 1st low engine breaking test, and from my understanding, there's not much else in the trans that can cause this issue. The computer seems to be seeing the parts involved functioning appropriately (just not at the right time, i.e. when in reverse). And so I'm feeling pretty confident we've got a problem in the valve body. Of course I could just go with a reman'd one at this point, but in for a dime-- I want to get to the bottom of this.

Sonnax has these valve body test cheat sheets: https://www.sonnax.com/tech_resources/430-ford-4r44e-4r55e-5r44e-5r55e-vacuum-test-guide

And this guy DIY'd a Sonnax vacuum test kit: https://ls1tech.com/forums/automatic-transmission/1893693-diy-vacuum-test-valve-body.html

And even better, the auto parts store has a vacuum pump in its loan-a-tool program, so I should be able to cobble together the setup tomorrow.

 

[Clayton]

Here are the results from EPC/CPP PIDs. I've been trying to figure out what to make of the two mismatching CPP readings, but haven't figured it out yet. The out of spec(high idle/low WOT) EPC pressures seem more interesting, though I'm not sure what to make of them either. Feeling more confident the problem is in the valve body though.

Ended up having to ordering parts for the vacuum tester, but should have it up and running by the end of the week. If there are no other external tests I can run while it's assembled, I'm going to pull the VB and see if anything jumps out.

 

[Orca]

I did some brief tests of my own today (2004 Ranger), but wasn't able to do it with the engine running and I wasn't using FORScan. Nevertheless, I can see that the "CPP/PNP" PID is behaving correctly as I move the gear selector from P -> R -> N -> D -> 2 -> 1. More specifically, that "flag" PID is 0 ("Neutral" had I been using FORScan) in both 'Park' and 'Neutral' and 1 ("Drive" in FORScan) in all other gear selector positions.

I won't go into the details now, but I am still suspicious about the "CPP/NDS" PID in FORScan. It just doesn't pass the "smell test", but I need to do some more testing before I say for sure. In fact, I think even the name is a typo. I suspect it's supposed to be "CPP/NSS".

I hope to do more testing, to also include EPC and other PIDs, with the engine running, later this week if I can get some time, hopefully with FORScan too. I will probably have more to add, in case it helps, later this week.

BTW, thanks for posting those links about vacuum testing. My transmission is working fine, but I'm trying to learn as much as I can, just in case of future problems.

 

[Clayton]

BTW, thanks for posting those links about vacuum testing. My transmission is working fine, but I'm trying to learn as much as I can, just in case of future problems.

Yeah man, I've seen so many of these threads hit dead ends with no resolution-- If I'm going to ask for help, hopefully I can leave a thread that can help someone else in the future, and even better if it helps you guys that are helping me along!

Just to clarify, you're saying your test verify my CPP/PNP results are as they should be? Out of curiosity, how'd you manage this without FORScan? I guess I don't even understand what this PID is looking at. What is in Neutral or Drive?

Further, you're saying CPP/NDS is likely similar to that Trans Range PID that is incorrectly labeled and/or not functional?

So last night I pulled the VB and found some potentially interesting stuff. It looks like it may have been dropped? The rear wall on the protruding section that extends next to the servo cover looks deformed with two hairline cracks. Neither seems to be all the way through, the adjacent valleys seem to just be retaining clips for the EPC booster valve and pressure reg valve. That said, that Sonnax vacuum testing sheet linked above does call out the EPC booster as a possible cause for a no reverse condition. The only other thing I noticed was the pictured possible gasket failures. Since all pieces were present, I'm unsure if the breakage was present, or if it was caused by disturbing the gasket in disassembly. Two of the spots are not pressurized, but mounting through holes. It is the bonded plate/gasket assembly. The one potential blowout is not adjacent to a passage called out by Sonnax for a no reverse condition, but the way everything is interconnected, it's hard to rule it out with my limited knowledge.

Lastly, as I was testing yesterday, I noticed a distinct hissing noise from under the cab when reverse was selected, and only when reverse was selected. Pressures are highest in reverse. I was alone and didn't feel safe crawling under while the truck was in gear, but it's possible this sound was coming from the pressure gauge that's hooked up to the EPC test port-- but I'm open to theories.

Onto the pics:

VB Damage:

A pic of another 5R55E VB that seems to show that the VB wasn't cast this way:

Gasket: