DKSF

Summary:
Been reading the useful threads about the same problem and the recommendation to replace the alarm control unit. My 1999 Boxster also had water under the seat where the ACU is and the circuit board was corroded. Obviously it won't crank.

I saw the price for new part is over $450 + labor to do the activation. Before going that route, I would like to replace a couple of relays that I see are corroded and didn't pass when I performed continuity test. The parts specifically are:
1) Siemens V23072 C1061 A108
2) NEC EP2-3L1S
note: parts seem no longer available so I am looking for equivalent version with vendors

Problem:
However, I noticed the board itself had some damage. I cant tell 100% where the 2 relays routes to for those 2 relays (there are several of the same relays, replacing the ones closest to the edge).

Request:
Wonder if someone has the board out and can take photo of the bottom of their ACU or access to the circuit diagram? I think I can fix it, but need to see the original to make sure it's done right. It says M535 on the box if that helps. Attaching pics, the relays are above the black plug in first pic and the back are in the rest of the pics...

Question:
As an aside, when I got the car, it only came with the spare (grey OEM) key without remote entry/lock. Is there anything inside the spare key part if I can open it up or is there just the blade?
If I fail to fix ACU, I'll prob bite bullet and get the remote key and activate it also at the same time. I'll be taking to dealer by Burlingame near San Francisco.

Thanks all.

DK

kderry

It's highly unlikely that the relays are bad because they are completely sealed (sonic welded at the bottom seam).
Do you have the diagrams for the relays? Without those, you won't know where to check for continuity.

Your money and time would be better spent buying a good used immobilizer and an EEPROM reader so that you can just install your current immobilizer's encoded data onto the new used immobilizer and not have to worry about keys or ECU matching.

DKSF

Thanks for response. I am asking for diagram so no I don't have it, but I can guess where it's supposed to lead from the board to do the test. It maybe hard to tell from the pic, but the soldering joints are so corroded that some are broken off the relays I mentioned so that's another obvious reason to replace. I don't think water got into the sealed part either but they are cheap to buy. It'd take less than 30 mins for me to do especially if I have can get a diagram or photo of the back of those relays.

I am not that familiar with using EEPROM. Set up with software seems like it could be a pain and I am not familiar with reading the hex keys to program it. Seems like even more trial and error process, If someone can share the process, I'd be interested in trying it out for sure.

Edit: KDerry, what are the chances the ROM is bad as well? I assume it should be low? I see some burn marks on the board altho light. To modify the idea, maybe it's possible to just remove the ROM on my board and put it in another working used condition board. I would need to know which chip is the ROM so will definitely need a diagram...

DKSF

Perused eBay for used immobilizers and saw a full set for sale with keys/locks/DME and ACU like below.
http://www.ebay.com/itm/Porsche-986-...hX4YPh&vxp=mtr

Seems like with this I can just install without needing dealer to activate the code? However, does anyone know if the ECU remembers the old car and so it still have issues connecting to new and won't be plug and play without dealer reactivating old code still so it's pointless? Does it have to be same year since engines are different?[/B]

The more I think of it, I am leaning toward buying a used ACU and taking it to the dealer to program since finding the diagram to id the ROM seems impossible. Dealer can reprogram used ACU?

Macster

My info is a used security module can't be moved to a another car.

You can buy the proper new security module from Pelican Parts.

Afterwards you'll require a dealer (or possibly a well equipped indy) service department "introduce" it to the car. This requires the tech use the PSTS/PIWIS diagnostic computer along with some codes he gets from the factory.

All keys will have to be supplied so he can add the key codes to the new security module.

Before you move ahead though consult with the tech to find out just what he needs to be sure you have everything.

DKSF

Thanks Macster, you are right, they can't be replaced even as a set because the system still remembers the old car info so still need to be reprogrammed by dealer. Just confirmed also with a tech who works on these. So hopefully this helps others in similar situation with the ACU looking at eBay parts.


The dealers in my area won't take the Pelican parts, say have to buy through them. But I see dealer price for some parts as cheap or cheaper than Pelicans like my ACU part #996-618-260-07. It's the service where they nail you though. There seems to be no DIY process to get around this unless KDerry mentioned.

So my options are back to:
1) Use old board and replace the relays, but there are a lot of corrosions and light burns even on parts that has continuity, still might be worth risk to try first since the relays are so cheap but seems they are sold only from vendors in Europe that I can find so far.

2) Buy used board and replace the ROM. Risk is used board may have issues but main issue is which chip has the ROM so without that info, I won't try it anyway. Would love to try the EEPROM idea from KDerry but don't really know much about hex keys reading and likely have to build own EEPROM for ROM.

3) Buy new parts, since I would like to get the new transmitter key anyway, I can get them to do activation for new key at the same time. Total I see online for the ACU/Key Blade/Transmitter comes out to hefty $750 without installation. Not sure what labour charges are but 1 dealer is $200+ with 2 hours est so I am looking at $1k bill for just this and hopefully no other issues. However, activation for keys are normally $110 or 30 min labour so I can prob do it below $1k.

Most likely I'll end up going option 1 first and end up with 3.

Macster

I'd skip step #1. From the pics I've seen of water damaged security modules replacement is the only true solution.

Not sure #2 would work. Some of what ties the security module to the car might be in OTP (one time programmable) memory that you can't erase/change. I'd not bother with a used security module unless I had good/make that high confidence what is being proposed be done can be done.

(My job involves programming embedded system micro-processors with code I have written. Even though I have all the equipment, and know-how, and the micro-processor maker documentation which spells out the steps to reset the OTP memory so it can be re-written I have found the OTP memory reset process doesn't work. This doesn't mean what is being proposed with a used security module won't work, it just means I'd have to see it work before I went down that path, unless, maybe, the used security module and the equipment to do what was necessary was provided at no cost. Then if it didn't work I'd just be out my time.)

To save yourself time and possibly money too, believe it or not, consider just going to #3.

It is unfortunate the security module got wet, but it happens. Best thing I think one can do is choose a path that has the best chance of getting the car back up and running again with no wonky security module (or other module) problems and put the incident behind him.

kderry

macster means well, but he is ill informed.

The EEPROM can be overwritten and the whole process takes 5 minutes. Anyone can do it. No experience or knowledge of electronics or coding is required. It is a simple copy and paste with a standard PC and an EEPROM reader/writer.

I won't share it here. If you want help, join the Boxster Tech Fans Facebook page and I'll help you. I'm an admin there and will add you if you request to join.
This forum is lame, which is why I rarely post here. Hardly any activity and half of that is by macster, who is wrong more than half the time.
That may seem a bit harsh, but it's 100% true.

Sorry macster, but you need a new hobby.

kderry

Nope.
Wirhout the relay diagrams, your continuity tests are just shots in the dark.

You should be able to figure out which relay is which by the pin locations.

It is kind of a moot point, though, as I'm sure you have damage that can't be repaired in between the board layers.




That is the end end of my help here. I'm not contributing to rennlist anymore.

Macster

If what is needed to make the used security module work with the "new" car is entirely contained in the EEPROM module, that's good news.

I was under the impression the DME also needed to be made aware of the new module.

If it doesn't that's even better news.

For the EEPROM to be overwritten means the EEPROM from the original security module must be readable. To be readable the security module must work to some level, at least supply proper power and ground to the EEPROM, ensure the reset line is not held in reset, and the other control, address, data lines are all unencombered by being kept in the wrong state.

I don't recall seeing the EEPROM socketed so unplugging it is not an option. I have managed to recover data from an EEPROM on a corroded circuit board -- not a auto security module though -- by having a lab assistant unsolder the EEPROM and then soldering it to a new circuity board. Given that the old security module doesn't work which is why the security module is being replaced suggests the attempt to read from the old EEPROM and transfer its contents to the new one could be a failure.

I admit I'm not always right. Wish I could be but ain't going to happen. However I thnk my record speaks for itself. I'm not often wrong or give the wrong information and when I do I admit it and try to correct it.

I tend to look upon solutions that consist of just a few rather esoteric pieces of info that are unfamiliar to the general auto owner -- like EEPROMs, reprogramming, EEPROM programmer, etc. -- with nothing more than just some high tech catch phrases but leaving the OP in the pretty much the same amount of darkness as before as not much help.

If you can provide the OP with more details and walk him through the process either here or on your own site that's fine.

However, I think it bad form to come a "competing" forum, run down the place, and offering that if someone wants the real info to come join another forum.

This doesn't mean you can't help direct the OP to where he could possibly find better info.

The only goal I have is in helping someone as best I can. If my info/experience -- while I have tons of experience reading/writing EEPROMs and FLASH, for a variety of microprocessors and non-volatile memory I've never bothered to attempt this with a security module or a DME -- is insufficient or inadequate then I welcome someone who can offer more help.

skullbyka

I had to replace my security module following water damage. Looking at eBay began to get confusing as some people said just replacing module would work , others said Security module,DME, and key head and steering lock module required.
Luckily came across a salvage company/guy here in uk who knows his stuff . On the listing for a Security module, key head and DME all taken from the same car he stated the set would only be good for same car model numbers and year etc .
I bought it and inserted the blade from my old key into the new key head,fitted the immobiliser box and DME ........worked immediately . Everything working as it should ����

marck

Nube to the forums here but I've got lock issue on a 98 Boxster I just got and found the following thread that may be of use on this issue. https://rennlist.com/forums/boxster-...-t-lock-2.html

My issue is passenger door won't lock at all, and nothing locks with key remote. All but passenger door make locking sounds. I'll post an actual question in a few days when I've looked into this issue more.

Any info posted on OP issue will likely be useful.

John Burr

My experience- at the risk of being corrected. I bought a used system off ebay - DME, Alarm module, keys, locks, steering wheel lock. I tried replacing components one by one. The easiest solution: replace alarm module, DME and steering wheel lock. Use the new key head and the old key blade as previously stated. Use the old ignition lock head (I'm sure there is a better name for this). By doing this with the key you do not need to replace the door lock or console lock and you can use your VIN if you need to order new keys. Make sure you note the VIN of the donor vehicle as this is needed for reprogramming. The car will operate without reprogramming, but the locks and windows will not work - a slightly different experience than other users and I'm not sure why