996 door lock not working even after replacing both side door locks

Hi guys, I hope someone technically inclined person can help me sort out this issue with locking. I have replaced both door locks & inner cable. My windows work as they should( comfort open & close) None of the doors locks with remote key, there is single beep. If I lock manually only driver door locks, passenger side door does not lock. When driver door is locked with key, it can be unlocked with key fob button. If I lock the doors using PIWIS drive links, both doors lock correctly, I believe it means electrically the circuit is ok & somehow control unit is not sending power to lock the doors. So removed the seat & carpet was not wet. Opened the control unit, this is how it looks like. I can not see any moisture on it, no bearing sign. There is some whitening, don't know if it is bad. While scanning the fault code is, Fault code 61- central locking limit position safe lock is not reached, switch position implausible. I did lock trunk & rear lid & doors, than checked the actual values, SOmething " input 1" & "input 2" is open, maybe that's why my door is not locking. In PIWIS, there is drive link to " secure door" & " lock door" . When I did " secure door" , my passenger side door locked & could not open from either side, somehow I managed to apply direct power & then it opened ( pin 1 & 9). Mechanically I had checked my door locks, works perfect. checked 3 fuses & fuse in control unit . My central locking switch also does not do anything while I press & hold it. Any guess guys . Thanks in advance.

Aftermarket door latches or OEM door latches? If they are aftermarket ones that is more than likely your issue. I replaced mine with aftermarket and had the same exact issue.

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Mine were OEM.

That board doesn't look healthy on the underside... When you say "OEM"? What brand are they? Pretty sure there is only aftermarket or genuine... Don't think you can get "OEM"

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they are VW, while I removed the old door lock, compared them & they were almost same.

First, the whitening on the underside of the board is sign of water corrosion. You need to clean that off with something meant for PCB board cleaning. Second, when it comes to electronics like this, I always bend over and buy them from the dealer. VW stuff might work on Audi, but not Porsches. Almost the same is close-but-no-cigar.

Almost the same is not the same. I have read many threads where someone used the VW/Audi and in the end it didn't work out. Like yelcab said above, this is one time to suck it up and buy OE Porsche. I had problems (after 20 years) with my drivers side door latch mechanism. I forked over the $$ for an OE Porsche door latch. Figure it would last another twenty years.......

I can confirm that a VW lock yields a single beep and an error code along the lines of 'safe(ty) position not reached' in durametric as I have one in the driver's side. However, remote (un)lock, window drop and stay dropped, (un)lock using key etc. all work. Here's an alternative to buying genuine porsche door locks. Check the microswitch (follow blue and red wires) on your porsche door locks. If you see worn microswitch head then I'd replace the microswitch with that off the VW door locks. That way you retain the required electronics but replace the worn switch on your porsche locks. Of course swapping the pcb from the porsche to vw lock yields all fresh mechanicals combined with the req'd pcb would be ideal but involves more disassembly. See post #49 for pics of switches and pcb https://rennlist.com/forums/996-forum/1062574-diy-996-door-latch-replacement-detailed-5.html

my lock had all kinds of weird behavior. The solder joints where the ckt board attaches to the connector were broken. very hard to see with the naked eye. Also, I have a spare (02 cab) I bought off ebay. I installed and tested it prior to fixing my original....if you're interested

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+ 1 the Porsche and VW locks in this instance are not the same unless you have an early 1997 Boxster without remotes then they are actually VW locks.

Thankyou guys for the input, I ordered new door locks from dealer. But the issue is same, dealer did country coding & now it is ok..

I just replaced my passenger doorlock with an OEM one. I had the 315Mhz security option. Now both my doors won't lock at all (by remote or central button). I suspect I need to take it to the dealer now to have it re-programmed. Btw, I replaced the doorlock because at the connection it was shorting out and not always droping the window when the door was open, that part now works.

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​​​​​​You'll need to define 'OEM' as others have tried 'OEM' locks and they haven't worked. There is nothing the dealership will be able to 'program' unless your remote key has stopped working.

Thankyou guys for your input, it was country coding that was required to be done, now it is working fine

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Country coding on the alarm box was stopping the doors from locking and unlocking?

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Ok so there is version coding that can be done but strange that would stop the doors from locking/unlocking

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Yeah it was stopping, I remember that my fault code was 61- if you see the description of fault code 61 in Porsche repair document it was different, but in PIWIS, it was showing a different description. This also indicated me that maybe something is wrong with control unit. After coding all work well, including the central locking switch in center console

I bet this is my issue to, I bought my parts from Rose Passion (France) and I live in USA. So probably have to fix the country code, @ dan_189 what tool is that you are using to change/check it? Is that a dealer thing?

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The screenshot above is PIWIS3 its the latest dealer tool. Although I think Durametric can do it as well though, i'd have to check. I find it odd that this is fixing issues although in PET2 there are two part numbers for left LHD and right LHD. One is listed for PR: 545 & 535 and the other has no notes against it. If you buy from Europe you might be getting the non-534/535 version.

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So I just realized that with ordering from the Rose Passion website with my car options (including the 315mhz m535 option) they send me part number 3B1 837 016M . When I asked the dealer what part I needed using my vin it was 3B1 837 016P . So maybe I just have the wrong part. It all fits just the car won't lock.

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PM me your VIN I'll have a look

When I replaced my door latches, there are different country codes. One seller told me they would not work in a US car, which was why he was selling them cheap. I suppose it makes sense that it could be re-coded. I have a similar situation, the remote does nothing, blinks once, but does nothing. So I have to use my key to manually lock, unlock. Which leaves the alarm on until you start the car, kind of a game to get in and start the car before the alarm goes off. Its on my list of things to fix, but given I dont need to lock it, its pretty far down. Front struts later this week and then I am done, the locks will be the last item. I could stand some new rotors, so researching those now.

Gdjsk, I stumbled on your post on Pelican as Rah. Your issue sounds much like something I have been having now for the last few months with my 2001 996. My alarm module is a 315MHz M535 996.618.262.01. Alarm module has had no water damage ever and I have inspected both sides of the PCB. I am able to lock the driver lock with the key but unable to lock either door or fuel cap with fob. I can unlock driver lock once locked with key, using the fob. So I just finished installing new original Porsche locks (9A7-837-015-03 for driver side and 3B1-837-016-P for passenger) and have exactly the same issue as before I started. The windows drop just fine depending on which door handle is pulled (and did so even with my original locks). Also my frunk and engine compartment lights no longer works but not sure if that is related. I noticed the frunk light flickering for a bit when this saga started. I have +12V going to both lights but just no ground which comes from the alarm module I believe. Both bulbs are fine. Durametric (enthusiast version) has been totally useless when working with this alarm module as it keeps freezing up, does not clear codes and does not show input signal states or actuate anything but just results in the lock buzzing sound. Anybody know if the IPAS codes are needed in order to change the country coding using PIWIS2? Also, anyone else have an issue with the country coding getting lost on its own? In my research, I found this post: ttps://www.renntech.org/topic/38717-door-locking-problems/ which too sounds similar and looks like the problem was fixed after reprogramming of the alarm module but not clear as to what was reprogrammed. The only upside to this nightmare is that I have become quite adept at removing and reinstalling door locks as I have pulled and reinstalled the driver side one a few times but with no change. If anyone else finds themselves running into this same problem and is looking for more info on symptoms, I have posted more details in these two locations: https://www.renntech.org/topic/57882...-light-issues/ https://rennlist.com/forums/996-foru...king-woes.html

Doing mine later this season. Good reference thread here vetfever

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Is there any fault code that you can read? If you actuate let's say driver side, passenger side makes buzzing sound. & Same for passenger side locking also ? Am I correct?

Thanks a lot for your reply to my PM, Gdjsk. With Durametric, sometimes it shows me fault codes and at other times it shows there are no fault codes (though I think there are but Durametric is having problems communicating with the alarm module is my guess). The codes that I have been able to read are: 61: Central locking limit position unlock not reached Occurance counter:24 47: Control locking synchronization Occurance counter:216 I have also got 46, 10,23,33,60 at times but these are not present any more. With Durametric, just going into the input state or actuation screen makes the brief buzzing sound where it sounds like it is trying to lock but instantly unlocks. Same when I click on any of the individual actuations. In my case, when I press the fob button, I hear the locks try to lock ie the buzzing sound but nothing happens. I currently have the new driver side one connected temporarily outside the door and will take a short video and try to post that so you can see what it is doing and also hear it. Based on what you indicated in the PM, I am beginning to think it might not be a wrong country coding issue in my case but perhaps some sort of problem in the alarm module itself (bad capacitor, cold solder solder joint etc.).

Here is brief recording showing what the driver side lock does when I press the button on the fob and the sound that it makes. Old locks had started making exactly the same sound. Gdjsk, do you recall with the wrong country code if you were hearing something like this or was it doing nothing at all in your case?

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I will try to get some flow chart to diagnose these fault code, will post here. Based upon description , While you press the key fob==locks try to lock, so alarm control unit is trying to lock both doors . I believe that it is worth a try to do code the alarm system, as it can result in strange behaviour. While coding is done, country coding is just a part of coding, I think for some reasons such as if battery is gone dead or sometime these control units need updated coding, that is covered by coding/ programming. It is not a big thing to do, just few steps in PIWIS. In my case I tested wires as well, as there are dedicated wire for both door locks to lock/unlock/secure/ remove secure lock, you can power them from connector of alarm control unit to check if wiring & door lock are 100% ok. Since both door locks are new, if I was in your place I would try this coding .

Thanks, I will have the coding checked using PIWIS and report back, You are correct, it does try to lock but does not succeed. I checked wiring too and all seems okay from the connectors at the alarm module to the 9 pin connector at the door lock, Being a US car, it does not have the safe or secure locking just locking I believe. I did not try to lock by applying voltage to the relevant pins on the connector but did test my original locks on a bench and was able to lock or unlock by applying voltage >3.5VDC and depending on polarity could make them lock or unlock.

It would totally make sense that Left hand drive and right hand drive would have the wiring flipped for Riverside lock vs passenger side lock. Wonder if you can swap the electronics off the two assemblies so the driver matches the driver side?

I do not think you can swap the electronics as they will physically not fit.

I was able to connect to the alarm module using PIWIS2. The car is a 2001 996 and a US model. PIWIS reports the alarm system as being an I48. When I checked coding, the country coding just said --- I changed it to USA as it is not a convertible. The only fault code I get is 61: central locking limit position safe lock not reached, switch position implausible I am able to clear the code but still unable to lock doors. I hear them attempt to lock but nothing happens. Using PIWIS drive links I was able to test that I could lock the fuel cap door but was not sure how to unlock it so just manually pushed the locking pin back as I did this test with the flap open. I could also actuate the turn indicator signals. I did not test locking the doors as based on Gdjsk’s post, I read they might stay locked and be problematic to unlock without applying voltage to the locks from the connector. I then monitored the input signals. I saw both doors being closed and locked which was not the case and opening or closing the doors would not result in a change in state from closed even though the relevant window would drop when the doors were open and go up when they were closed indicating the microswitches were fine (I replaced both locks with new Porsche locks). So this would perhaps explain the code 61 as the alarm system is seeing the doors as being closed and locked and also not changing state when trying to unlock. Additionally the frunk and engine compartment lights stopped working (flickering initially and then stopping totally) when the initial door locking issues started a couple of months back. The alarm system also sees the front luggage compartment and the rear luggage compartment/engine compartments as being closed when they are not and opening or closing does not result in a change in state. This would explain why the lights do not turn on either because it only sees them as being closed. The only inputs that I could get the state to change and display correctly in PIWIS were: -Buttons 1 and 2 on transmitters (change from not actuated to actuated when the relevant button on the fob is pressed) -Central locking system button which changes between not actuated and (close) actuated or (open) actuated -Front lid release and read lid release buttons both work and updated correctly -With the key in the driver side door lock, the door lock barrel signal changes between not actuated to (close) actuated or (open) actuated. Again there has never been any water damage with the M535 alarm module. I have resoldered all through hole connections on both connectors where they connect to the PCB as well as all through hole components such as the relays. I have replaced the electrolytic capacitor. Inspected all surface mount components with a microscope and do not see any bad solder joints. All fuses in car and the one on the alarm module are good. I had issues with my ignition switch where it would not release the key and so had replaced it with a Uro one last year and have not had any problems with that since. Battery is 1 year old and been recently charged as well. Anything else I could be missing in terms of some ground or supply signal to the alarm module? Or has something failed on the alarm module? After replacing my locks which it now turns out was not necessary, looks like my only option now is to replace the alarm module. I just hope after I do that, I am not in the same situation.

What are the part numbers for each side? Did you order them by your VIN?

The part numbers for the locks were 9A783701503 for driver and 3B1837016P for passenger and yes I did order them based on the VIN.

I think you need to start looking for broken or shorted wires.

I did check all the wiring and the state of the signals for the door closed and lock states and they were all fine as was the frunk closed signal. So ended up getting a new alarm module installed a few days back and that has fixed all the issues. Doors and fuel cap lock again and the frunk light works as well. So it was a strange failure mode of the alarm module where only certain inputs stopped working. Glad this one is resolved. This also means that my original door locks were perfectly fine and not the problem at all. Thanks everyone for your help and advice with this one.

Hey I also bought my door lock from Rose Passion, replaced the passenger door lock with it and now it also will not lock. How did you end up resolving your issue?

How were you able to country code? I asked my mechanic and he told me that was beyond what they are able to do.