Yeah, that's unfortunate. The car shifts fine when it's not glitching though, so I think this is a fixable issue that does not require trans replacement.One big issue in attempting to fix the trans is that the DCT trans have low 'fix rates' as a product across all manufacturers. Going one level deeper on FCA products (Fiat-Chrysler) is that they tried to resolve many mechanical issues by fixing the original version (same architecture) found in other FCA products... to repeated failure and triggering the Lemon Law... which saw them ordered, by court/judge, to cease repairs and only replace them with updated units.
This was good news for those affected and chasing their tails under warranty, as repair after repair failed. There is bad news with that: Now there is no established knowledgebase or supply chain to allow repairs. The seeds of repair are barely at sprout level. For a trans used so widely, the reparability should be high. It exists, but it is primitive and limited. An actuator here or there, and lots of 'let's try this' ... which is thousands of dollars which might never avoid the cost of getting a replacement, but is just money piled on top.
They proved they are incapable of fixing them; they triggered the lemon law as a result; the courts ordered them to cease repairs, and now you are left holding the bag, because you seek repairs. Can't blame the courts, as FCA proved incapable, and there does not seem to be real hope beyond a crapshoot anywhere else.
I didn't ask, but when I brought it into the dealer, they suggested that they may reset the contact points once they had looked at it. It's not clear if they actually did this though.Have you asked for a transmission recalibration? Something about adjusting the kiss points of the clutches. My tech gave one to mine last year, I thought as a preventative measure, because I really couldn’t detect anything wrong with it. It did smooth out the changes in certain circumstances. These things are too clever for their own good, and ours.
I have 18K miles on mine. Never been to a track day as far as I know, although I did run an autocross with it back in February.How many miles do you have on your 4C, and have you ever tracked it? I'm at 12K on my 2016 so far zero issues but planning to have bolt tightening and other service performed soon in Atlanta. Will definitely be asking about the DCT.
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Yes, I should add the TCM as a potential culprit. I will definitely pull off the shield and connectors and inspect the connections for water intrusion, but I'm guessing it's not the issue here (see below).All things considered.... reading all the information again... a mechanical issue should not come/go... and you're a 2016, but with right software in the TCM.
Has anyone considered replacing the Trans Control Module (TCM)? 2015-2016 TCMs could be compromised by water.
I put the car on a Battery Tender after the first occurrence just in case, but it didn't prevent the last two happenings. I'm still keeping the battery on the list of problem areas though. The AZ heat is known to kill batteries and if this is the factory battery, it's end-of-life anyway.So i had the Christmas tree lights happen once in the past. So many lights i could not keep up with them all... Freaked me out. I believe it was voltage related. Put it on the tender and never seen this again. Been a year or so. Just had my battery changed also last week. In for service but felt since it was a 2016 even thou they told me battery was fine these cars are finicky when it come to voltages.
I could definitely see this being an issue, as I actually lived through this problem (water intrusion via wire harnesses) with an automotive component I designed at my job several years ago. However, I would be surprised if it's the problem here - I live in AZ where it's very dry all the time, and when I wash the car I use Optimum No-Rinse, which means that I don't even hose the car down. So if any water is getting in the engine bay, it's a few drops at best. The car did come from Florida and Virginia though, so it's not impossible there was existing corrosion before I bought it.My car is also MY2016
I'm pretty sure the problem some have is because of the routing of the wire to the TCU. 100% sure water gets into the back of the connector and migrates into the connector on mine.
I plan on flipping my TCU over so the connectors are facing down.
Most of the body computers and wire harnesses I've been offered also appear to show issues with water running down the wire harness corroding connections, obviously creating a range of electrical issues.
Well I'm trying to avoid just throwing (expensive) parts at the car, but to your point, a TCU is definitely cheaper than an actuator. You're also right that at this point I have no way of knowing whether the issue causing the fault is at the sensor or the TCU. Maybe if someone has a spare TCU laying around that they would let me borrow I could test that theory?@nate37 have you considered just replacing the TCU itself? Wondering if everything is actually fine, but there's just weird computer gremlins? The reason that I ask is, my understanding was that they won't sell the actuator or parts of the trans, and will only replace the full unit?
Yes, I agree. Been meaning to hit up @AlfaRomeoCares to see if they have any additional knowledge or could at least help me find a replacement sensor module, but haven't had a chance yet.I would take up Alfa Romeo Care up on their offer for help. In the background, with the details you have, they will reach out to their network to see if anyone solved a similar problem. I am a huge critic of service I receiver everywhere, but they are great and responsive.
Don't know what to say about the actuator gambit, other than Amazon has a good return policy. Maybe use it as nothing more than a test item to clear a variable? -- but I don't know about compatibility.
I haven't yet. My DIY timing belt change has been a disaster (see my other thread), so I'm still trying to get that sorted before I come back to this issue. Once I finish the belt (almost done) I plan to take off the driver side quarter panel so I can inspect the TCU connections, chassis ground connections, and as much of the actuator wiring harness as I can get to. Definitely doing this before I start taking the transmission apart. From what I can see, removing the actuator might be a pain. Not a lot of room to maneuver it out.Were you able to rule out the wiring harness connections to the TCU (corrosion issue)?
I know that you said it wasn't likely from your ownership, but the car's past life and the heat where you live might have caused latent corrosion, just enough to cause this intermittent gremlin.
I would think this a worthwhile check before starting to disassemble parts of the transmission.
I know that my Foxwell reader has the all the transmission re-learns included in it, and it looks like there are several re-learn procedures for the ECU also. Seems like the easiest way to do it.Good information.
To trigger these re-learns, they connected their system, or just disconnected the battery?
I assume the former (I think that the only transmission re-learn you can do without the diagnostic equipment is the "fine clutch adjustment", but would be happy to be corrected).
Sorry to hear you're having the same issues. I suspect we will see more cars have this problem as time goes on. Good idea on the testing - hopefully that helps someone in the future.Hi, My 4C has 70.000 Km and I experience the same problems now. I am using the Multiscan 4.7R3 tool and did all Adjustements. In the Production/Service final calibration procedure, all elektrovalves, potentiometers and mechanical components of the whole actuation unit, are tested. So, in your case, it would also test the integrated sensor module. So my suggestion is to run this test and than do the clutch self-calibration enable. In my case I first got the error code related to the electropump of the power unit. I changed the electropump,the accumulator and the elektronic control unit of the elektropump, but without any succes. During a trip in the Italian mountains, I got the same problem. Now I am going to replace the clutch, because with 70K and at least 50% driving in the mountains, I think the best is gon and the clutch is worn.
Ah sorry to hear you're also having issues. When my car would fault I would lose R, 1, 3, and 5. These gears are all on the same shaft, so my guess is that the gear position sensor on this shaft would fault and the TCM would lock out all those gears to preserve the transmission.When you were having issues was reverse available? My car is currently in the shop and I am trying to help the tech with any guidance as far as known issues.
