01SBox

If I replace my transmission, do I need to replace the tiptronic control module?

Assuming the control module is 100% fine, I'm wondering if the transmission is somehow "coded" to the module..this is an 01 Boxster S

thanks in advance

Tsmith84

nope, you can just replace the transmission. I would recommend having the adaptions reset though. The control module adapts to clearances in clutches and such that will not be the same in your new tranny. It will re-adapt to the new transmission but not as soon as if you reset it. Your dealer can do this or your repair shop with Porsche scan tool software such as durametric.

jondel

Hi everyone,

New to the forum have a 1998 - 986 and A few questions on the Tip please.

1/ Just wondering what exactly is the function of the Control Module for the Tip?
2/ Where exactly is the Tip Module located?
3/ Is it simple to replace for a novice and If replaced with another Module (Not new) are they all compatible/the same between 1997 - 2004 Boxster Models?
4/ After replacement will anything need to be reset/codes cleared etc.?
5/ Can the module be responsible for flaring between gears?

Thank You

Macster

The exact function (functions) of the TCU are too complex to cover here, even if I knew them all which I don't.

The very brief version is the TCU manages the automatic shifting behavior of the Tip based on a number of inputs.

Needless to say proper operation of the Tip depends upon a correctly functioning TCU and of course its population of sensors. Since the TCU receives some of its input from the DME and the DME derives some of these from its sensors the sensors connected to the DME need to be in good working order, as well.

The TCU is located on the rear trunk bulkhead next to, to the right of, the DME module.

The removal and installation of the TCU is not that difficult, but it is not a process to be taken lightly. First, I would never ever expose this module, and touch it, or remove it unless it was absolutely required.

The TCU (like the DME) is a very complex and delicate in some respects computer, and bend/break a pin removing it, or installing it, static discharge into any connector pin, and you can ruin a $1000 or more (probably more) electronic control module.

As for which TCU you can use, all I can offer is you need to consult with a Porsche parts specialist and get the part number of the TCU or TCU's that are compatible with your car based on its VIN and other info, and limit yourself to using TCU with the proper part number. I can almost assure you later model TCU's will not be compatible with your car and its TCU requirements.

Except for the possible need to reset the TCU after installing it, I"m not aware of any other programming necessary to get the new TCU to work with the car, but you need to consult with a real Porsche tech on this question.

If one is going to the trouble and expense of replacing or swapping a TCU one should strive to learn exactly what is required to effect a trouble free and successful TCU swap. This is not the time to see what one can get away with.

As the flaring between shifts, I would have to offer the opinion the TCU is not responsible for this behavior.

However, a scan of the TCU using the proper Porsche diagnostics computer and the reading of any active/pending codes would be a good step. If the TCU was responsible for this behavior the odds are high an error code (or codes) would be present.

At the same time you could ask the tech about the behavior. Chances are he has seen this before and would be able to tell you what is the cause.

Based on my info, 2nd hand info, when a Tip starts acting up and there are no error warnings or error codes from the TCU (or sometimes even if there are) the problem is a mechanical/hydraulic problem with the Tip and not a TCU problem. In short the Tip is wearing out or has worn out at least someplace.

If the Tip is the problem, all is not lost. The Tip is a common transmission, made by ZF, and similar examples are used in a number of other cars. My Porsche tech buddies tell me that almost every major urban center has at least one highly skilled/qualified Tip (ZF) transmission repair shop. Often what happens is the car is brought to the dealer to have the tech remove the Tip, then the Tip is picked up and rebuilt and returned to the dealer for installation.

jondel

Thank you Macster for the time you took to help me with these questions much appreciated!

I have had the car for around 1 year now and I took the car to 4 different so called Porsche specialists. The Tip was flaring between 2nd and 3rd and then even started to 4th. and if I take off too hard even thudded into gear, however when I was in Auto and driving at around 60mph, if I put my foot down the Tip responds great and drops down to 3rd without any problems during acceleration. Driving it in Auto during gear changes around traffic, was uncomfortable to say the least, so I started driving it in manual and taking it to around 4k rpm between shifts which helped somewhat.

The first 'specialist' garage I took it to suggested a fluid and filter change is probably all it needed so $700 later the Tip still felt the same. They did add however it could take up to 500 miles of driving and another fluid change for it to improve bzzzzz wrong again LOL.

So now I'm in the hole over $1,000 and the tip is the same. The other 3 specialist mechanics were basically no better and as no error codes were showing they suggested a full rebuild or change over Tip was in order, we're talking many thousands of dollars here.

Anyway, I kept reading up as much as I could about Tips in Boxsters and asking questions, until one night around midnight a couple of weeks ago, I was reading up on the cars Fuses. What struck me was fuse E10 Tiptronic Controller Fuse 15AMP.

I thought to myself I'll check the fuse tomorrow, but surely 4 specialists wouldn't have gone through all that with me and not checked the fuse. I couldn't sleep thinking about this, so I went to the garage crawled into the where the fuses are and started counting and when I got to Fuse E10, well there wasn't one. E10 Fuse was missing. I quickly found a 15AMP fuse and put into the slot. Next morning I took the car for a drive, very different driving experience this time. Nowhere near as much flaring and no thudding into gears on the way up. There's still some flare between 2nd and 3rd and 3rd and 4th but nothing like it was before I installed the fuse. That's why I asked if the Module could be playing up. What I can't understand is who would have removed the fuse in the first place and why wouldn't it have been replaced? And why oh why did 4 different Porsche mechanics no check that? Blows my mind how incompetent these people are all except in taking your money! In that area they are extremely skilled!

I guess a motto here is 'Don't trust or believe everything a mechanic will tell you'! Even 4 of them

Again thanks for your post Macster I do appreciate your time and input!

Macster

Thanks for the update.

It is unfortunate that not one of the 4 techs was able to help you. But your perseverance paid off.

As for the fuse...

My references label fuse E10: PSM switch. The only fuse I see that might have something to do with the Tip is fuse B1: Instruments, OBD II (diagnostics plug), Tiptronic, PSM.

My Boxster doesn't have PSM, though maybe my Turbo has it, but regardless I am not PSM savvy. Perhaps the previous owner removed the E10 fuse to keep PSM off all the time? Just a WAG, admittedly.

jondel

You are indeed correct Macster, B1 Does refer to the items you mentioned except I don't see the PSM option anywhere I don't think this is a standard, in base models possibly an optional extra however TC Button could stand for traction control button, which I don't have anyway. Nevertheless that fuse B1 in my car was in place. ABS traction control is B9 on my car. While there I checked all other fuses relevant to my model. My Workshop manual (see copies attached) shows E10 as the Tiptronic Control Unit.