Peter Ogden

I'd guess that the lock drive motor is faulty on your replacement unit, pulling down both units when plugged in. Your original unit has a faulty microswitch that stops the window dropping. If you are handy with a soldering iron, you could probably make one good unit out of the two, by removing the microswitch from your replacement unit and replacing the faulty switch in your original unit. Otherwise, return your replacement unit for a good one.

DBJoe996

^^ I have to agree. The door latch mechanism is a go or no go situation. If a brand new unit doesn't work right, it never will. What type of replacement door latch did you get? From where? Is it the correct door latch, because there are different ones for driver/passenger doors (and I think LHD or RHD is a criteria as well).

Teekster

2nd new unit from sonnen Porsche had the same behavior. I had a separate thread asking if anyone knew if there was a difference between part numbers (big price difference). No real responses. I guess I know now.

Peter Ogden

It depends on which specific part numbers you are talking about. There are specific units for right hand drive (RHD) cars and left hand drive (LHD) cars, as well as specific units for the left hand door and right hand door of each variant. So you must get the one that suits your car and door.

As an example, the left hand unit for a RHD car will fit, but not work in a LHD car. If you have the original unit out of the car, take note of the part number. If you are substituting a VW part for the Porsche part, only the first 3 characters differ. The last part of the part number should be the same.

See my post above.

Teekster

Mine is definitely a LHD car, but it has a different part number than those listed earlier in this thread. I tried the one that was listed here, but it didn’t work. It was less than half the price that my model #. Mine is 3b1837016p. As far as I can tell, there is a vw part with the same part number, less the p. The Porsche part varies from $350-450. I just ordered a used one from eBay. If that fails, does anyone think the vw part will work?

Peter Ogden

So according to the Porsche Parts List (PET), the part number listed is 3B1 837 016 M, which is for a Left Hand Drive 996, Right Side (Passenger) Door with M534/M535 Alarm System (see screen grab below). The letter following the part number usually denotes a revision of the design, so P would be a more recent variant than M.


Extract from PET for 996

In my case, the units I replaced were 8N2 837 015 and 8N2 837 016 on my '99 Boxster, and 8N2 837 016 on my '02 996 - my cars are Right Hand Drive (Australia). My Boxster had an after-market alarm system, so wasn't using the Porsche Alarm System and the VW units worked perfectly. My 996 does have a Porsche Alarm System and the drivers side VW substitution works great, but I haven't yet needed to replace the passenger side unit, so I don't know if the original unit in mine is the 8N2 or the 3B2 variant. I may also have the same issue as you if/when I have to change the passenger side unit. I get the feeling that the VW unit with the same part number (minus the letter) should work fine (and I would personally try one of those before paying the Porsche tax), but it is only a guess as I haven't had direct experience. Sorry I can't help further.

Teekster

Thanks for the reply. Cheap eBay used replacement with the same part number solved all of the problems. No real Porsche tax paid.

hardtailer

Had to try this myself after reading your findings as I remembered it differently and indeed I can unlock and lock the driver's door turning the key without power (battery disconnected) on my 99 Carrera.

ExileOnMainSt

I was looking at this to save some money. So everything else is the same for the S and Cab S not diff for any other models? I have a 2009 Cab S.

Thanks

Peter Ogden

The information was applicable to the 996. 2009 would make your car a 997, wouldn't it?

The chances are good that there is an equivalent VW unit for the 997, but I couldn't say for certain. Get the original part number from the 997 PET and try searching the internet for parts that match the last part of your part number. If you find an alternate, just make sure it is for the correct side and for LHD (assuming your car is LHD). It may well be that the 997 uses the same units as the 996, but as I don't have a 997, I haven't checked.

AGGNES

Great thread - Thanks for all the information and detailed steps - My problem has been resolved after following these steps to replace the passenger lock assembly. After doing this once if the other side fails I will use the VW part as it was easy to switch the piece from the old lock mechanism to the new lock mechanism. I had purchased a used part off fleabay but in the future I will order the VW part.

Luca Essig

Does anyone have the link for the eBay part?

Luca Essig

I have replaced both of my door latches. It fixed the window dropping issue, but now I can’t lock the car. It sounds like it locks, unlocks and then honks and stays open. The latch doesn’t want to turn over. Any idea what this could be? I already checked everything, and it looks like it is all connected.

Davids996

Just replaced mine too...bought off eBay and works awesome. Actually helped the door align better...interesting.

One word of caution (wisdom)...inside door is sharp...not wearing gloves, slipped when pulling something and slit my hand wide open. you can imagine my wife's joy... Actually had my daughter drive me to urgent care for 3 quick stiches. Oh, and yes, works perfectly now...the door latch that is.

thebutterson

I just installed the VW equivalent part which I got off ebay and have a similar issue. As soon as I connect it Durametric will show a fault in Alarm I32 as Fault Code 012 Wrong Door Lock Module, or something similar to that. If I plug my OE unit back in the fault is no longer active. With the VW part in the electronic locks will not work with the key. I can use durametric to lock them but I still get a fault.

Has anyone seen that?

I think I'm going to order a replacement, plug it in, and verify I don't get a fault before I actually install it.