Transmission shift solenoid

Yeah I can do that lol, I use a volt meter at work occasionally to test solid state relays. Now my issue Im worried about, is if it’s the wiring…what do I do??? That’s a mess I’m not sure I trust my skills to deal with since it’s electrical. I’m more of a wrench monkey… I can do basic soldering but that’s not gonna really help with wires that will be sitting in fluid? And as for the parts stores…umm i can try see if the solenoids is at O’Reilly’s, but Im not really able to wait on parts to come out to me since this car is my only means of transportation out here in the boonies.

Most parts houses offer a economy line and a better line, stay away from the economy line…

You should be able to test the solenoids to see if they are stuck open or closed…

The testing of on/off solenoids is straightforward . Pressure should be applied to the inlet, and if it is normally closed, you should not see pressure at the outlet. Once energized, you should see pressure at the outlet. For a normally open solenoid, the opposite is true.

If you don’t trust your skills then it may be time to take it to a transmission shop…

I would think that shift solenoids would have a open/close rate (like speed or timing) and being to slow could cause shifting issues, throw codes, cheap solenoids might work in theory but not in application, which could cause a flair up (slipping) if not fast enough…

Man thank you so much that actually clears up a lot for me. I’m thinking one of two things thanks to your advice and information, either a, the solenoids I got were cheap and like you said they are not effective, or there’s an issue with he wiring from me not correctly cleaning and connecting it. So I will drop the pan and solenoids and test em tonight for pressure and see what happens. I just thought about something too…
I change a and b and I’m getting two codes of the same number, this could be because it’s reading a code for both solenoids?? If true then maybe I did not connect them correctly or I bought cheap parts… what do you think? Cause it was reading two codes before the swap too…

Just me but I’m not sure I would trust an eBay supplier. Go to all that work and find out it was made in China. Wire harnesses can be replaced but a certain amount of disassembly required. When Rollie the thief did my transmission, I told him I wanted a new wire harness put in while it was apart. Seven weeks later he claimed he put one in but the 4th gear solenoid didn’t work. Another shop had to drop everything again to put a new harness in. And the harness was a Detroit only item so I know Rollie lied. Trying to save $100 cost me another $300 to fix it.

Bottom line, quality oem part, and good trans shop are your friends.

I would check the wiring harness while the pan is dropped and solenoids are unplugged and make sure you have good continuedly on the wiring harness as Mustangman has already mentioned, as well as all the pins in the connecter (plugs) to make sure none are bent or broke etc…

Normally when the same code shows up more then once it is a history code, pending code and or a hard code… Basically everything has it’s own designated code number…

Just don’t forget you can still have wiring issues as Mustangman mentioned, mice, rats, squirrels, rabbits and any animal like that enjoy a wiring snack from time to time… lol… As well as other wiring (broken, corroded) issues as well as TCM issues… Worst case something internal broke…

Can’t quite make it out, but I presume OP’s car is a 2015 Ford Focus ZX4. I’m not seeing that code applicable for a 2015 Focus in its L4-2 L configuration.

Suggest OP review this recent thread for reference, not same problem, but similar, on Ford Focus.

Sorry friend it’s for a 2005 Ford focus zx4 Se 2.0L

Copy that. I’m getting higher quality solenoids from the a reputable companyi found costing almost 60 dollars a piece. When they come in I’ll drop the pan and use a volt meter to see if they getting continuity as was suggested, and I do know the wiring harness inside the pan is intact, because I took a picture of the job while I was doing. Totally forgot but I checked the wires in the photo and they all are intact but wet, so I’ll do checks for grounding possibilities and possible connection issues too.

This did not help as I have older model car and the code I get is the shift solenoid not a friction one.

With car off, parked in P, & the proper scan tool appears to be possible to command each selenoid (a,b,c,d, & e) on & off and verify it actually switches state. Seems a good place to start the diagnosis. Besides that about all a diy’er can do is to look at the electrical connector for problems (bent or corroded pins etc), and to remove the pan for a look-see at the fluid condition, sediment, metal shavings etc. New fluid & replace the transmission filter. If no joy, next step is to replace the solenoid on flyer. Common sense, if replacing A, good idea to also replace B. B failure probably not far behind. Note that a faulty solenoid could still pass a windings resistance test.

Fairly simple enough, I have this information from the scanner tool I thought would work for some stuff but I don’t know exactly what I’m looking for as far as being able to tell if a shift solenoid is opening or not. so short of doing everything I just did over again, this is what’s being pulled up on the tool. After I did the replacement this code still came up. I’ve replaced a and b cause like you said, common sense said if a is going out b is likely to follow. So I’m at a loss since visually it doesn’t seem an issue.

This is under the pan. And before you ask yes I connected the purple wire before putting it back together lol. Visually nothing seems off or broken

It’s sounding more and more like a hydraulics problem. Think of plumbing, pipes and valves. If a valve opens ok, but the pipe going to it, or going away is clogged, working valve still does nothing. If the scan tool tests says the valve is opening and closing on command like it should, likely something is clogged inside the transmission valve body.

Ah see that’ clogged thing shouldn’t be the issue I’m having since thi tool is saying it’s stuck in mainly off position but that does give me an idea… How can I diy flush out the lines ?? Or would that cause more damage

I don’t know if I’m explaining it right but I’ve been hard shifting between gears and at one point I was slipping the gear, and then the only codes being given is the solenoids. I tried a cheap one tool and it gave the code p0751 which is the solenoid performance a stuck off position every time I clear it it comes back after the hard shift that it’s stuck off. So I change the solenoids and the filter and fluid and I hard shift more frequently with the same exact code coming up. since I came back from Town with that code I used this new innova scanner tool and it gives me the same code and recommends changing the solenoids again. Now I fully get your thoughts on it being the hydraulics in it but what I’m feeling and dealing with says more than likely bad/imroper connections or cheap parts. But since I’m gonna have the pan off anyways and I don’t wanna come behind myself again,.do you recommend trying to potentially unclog the lines, and if so what’s the best way to go about that??

Never mind below reply, somehow got missed up on the year of OP’s vehicle…

OK, we need to back up and start over here, those are not shift solenoids as in the traditional on/off solenoid allowing fluid flow… These are 3 phase electric motors (Solenoid Valve Clutch Actuators) that drive gears to move the clutch forks to move the throw out bearings to engage the pressure plate to the clutch disc X2 in the DCT setup… so NO oil flow through them…

Think of this as a manual transmission/transaxle (because it is) and NOT an automatic…

It is a very simple design in a very complicated way… lol
The clutch and shift arms are all automatically controlled by gears and the 2 solenoid motors, no fluid drive/flow in the transaxle…

I am thinking that your code P0751 solenoid performance a stuck off position, on a automatic transmission means just that, a stuck solenoid open or closed, on your transmission that can not be the case as there is no fluid flow… So that make it more of a solenoid performance code, the performance is the solenoid (actuator) spinning to slow or to fast, to fast is applying the clutch to fast or hard like dumping the clutch, to slow would be a soft slipping feel like riding the clutch allowing it to slip to much… As the TCM controls the speed of the solenoid(s) (actuator) then if the solenoid (actuator) is mainly acting up in 4th gear it sounds to me like the TCM is either bad or needs to be flashed… As one solenoid (actuator) control 1,3,5 and the other one controls2,4, and 6 gears respectively… If one solenoid (actuator) was bad it would stand to reason half your gears would be acting up…

Here is a pretty good video on your transaxle and how it works, a little slow and boring but still good…

EDIT: Not sure about the 3 phase part of the motor thing but they are brushless motors…

Do you know if it has an open circuit (resistance too high) or circuit shorted (resistance too low) code, or does stuck off mean open circuit?

Just a short question/comment but it sounds like the solenoids/motors replaced are not the solenoids causing the code. So naturally the problem is not fixed and the replacement again and wire harness is a wild goose chase? Was a factory manual used? Maybe I read it all wrong. Just another reason I don’t mess with transmissions.

This to answer bing’s question about DCT, And below reply has nothing to do with OP’s post, somehow got missed up on the year of OP’s vehicle…

There are a total of 4 electric motors, 2 that control the shifting forks (shift actuator) and those 2 motors are part of the TCM…
The other 2 motors are what is called the solenoid (clutch actuator) and is what the OP has already replaced…

The solenoids (clutch actuator) takes the place of your foot pressing the clutch pedal, or better yet releasing the clutch pedal as the pressure plates are in the release (free spinning mode) normally, when the solenoid (clutch actuator) engages it is like you letting out on the clutch…

A DCT 6 speed transmission/transaxle is like having 2 seperate 3 speed (different ratios, not counting reverse) transmissions with 2 seperate clutch assembly’s including seperate throw out bearings all in one case controlled buy a common controller (TCM)…
And the TCM shifter actuators (motors) take the place of you manually shifting the gears…

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This vehicle is a 2005 model year vehicle, 2 I 05 is a misprint. ZX4 trim level was used in the 2000’s.