Alarm unit water damage - My car won't start and I am in a tough s

[psperl]

Long time lurker here. Could really use some help. I've read most of the posts here (and on rennlist) about this more common than it should be issue, and have tried most of the suggestions.

A month ago I woke up in the middle of the night during an 11 inch rainstorm to the sound of my 1999 non e-gas 996 alarm going off. I had to disconnect the battery to get it to stop. The rain flooded the cabin and corroded the alarm unit under the driver seat. After doing some research and learning that the alarm unit, DME, and key are a matched set, I decided to purchase a set from a guy on ebay pulled from a canadian 996 (my car is US, I wonder if that is ok). The guy on ebay was helpful during initial debugging and said he tested the units in his car personally before shipping. I have no reason to suspect he is being dishonest.

I installed the new alarm unit and DME, and the interior effects are working again. Actually, the only thing that isn't working is that the car won't crank. The key remote unlocks/locks the door, everything seems good.

If I bridge the starter relay and turn the key the car cranks but doesn't start. The clutch switch works if I measure across it with a multimeter. I figure the ignition switch is good or it wouldn't crank when I bridge the starter relay.

My OBD-II reader showed no codes, so I bought a Durametric cable. It showed a slew of alarm and DME codes, mostly related to their being a loss of power, and some immobilizer codes as well. I cleared everything to get a fresh diagnosis, but no codes came back after a week of trying to start the car. I did get a W lead disconnected (or something llike that, I32 W Lead) almost immediately after clearing the alarm unit codes, but I cleared it again and they haven't come back.

So I've got no faults on the durametric, and my only guess is that the DME is immobilized quietly. Do you guys think I could be missing something? Would programming the DME to ignore the immobilizer be helpful? I read this was possible in another thread. I have NO fear of the car being stolen. I really fear going to the dealership, those guys always get the best of me. Thanks in advance guys, I have reached the limits of my knowledge.

-Pete

btw: The original motor suffered an intermediate shaft failure, and the new engine bent a valve 200 miles out of the shop, which porsche refused to cover the labor on. Now this water damage/immobilizer nonsense. I am not lucky.

[goldenwarrior1]

Loren will probably chime in here but I believe your DME needs to be programmed with a PIWIS to enter your VIN into the immobilizer. Without that it will never start.

[Loren]

Did you get the keys from the donor car? They have an immobilizer pill that allows the car to start.

Without the keys you would need to get IPAS codes for your car (keys) and the donor DME/alarm so they they can be programmed together (using a PST2 or PIWIS tester).

To reprogram a DME/alarm you need the old codes AND the new codes.

[psperl]

I bought the DME, Alarm Unit, and key pill from a (canadian) donor car, so they all match. I can't personally prove that they all match, but the provided key does unlock/lock the doors with the alarm unit installed. My original key pill does nothing, so that seems right.

Conventional wisdom is to get someone with a PIWIS or PTS2 to program the DME to the alarm unit, but I am trying to avoid the dealers. Those guys have done such dirty things to me in the past that I have a hard time going back.

[logray]

If all of those things were sold as a set from the same car I don't see why it wouldn't start assuming you installed both the DME and alarm unit and the DME is the right one for your engine.

Without a PST2/PIWIS though to validate all of the codes are in line and the pill does match, it's impossible without those tools.

I am wondering if the car has some other water damage.

Perhaps the airbag module is preventing the car from starting. Have you noticed anything strange about the windows rolling down on their own, or an airbag light on the dash? the A/B module is under the drivers seat as well IIRC.

edit: also I am going to do some research on the Canada thing, if they use a different frequency for the transponder, that might be an issue...

Edited September 21, 2011 by logray

[logray]

Ok, USA uses 315mhz for the key transponder, which is option code m535. The rest of the world uses 433mhz, or option code m534.

Do you happen to have the P/N on your alarm unit? I am guessing it is going to be m534 option code.

I am wondering if the pill antenna (and/or other parts) are setup for 315 mhz (USA) and therefore ignoring the 433mhz signal coming from the key. Just a theory here on that one, but maybe even though the alarm unit is now 433mhz there is something else in the car that needs to be changed out as well to receive that signal, perhaps something near the ignition switch or the length of the antenna needs to be modified for that frequency???

Also using your Durametric are you able to connect to your airbag module? Do you see any fault codes in there?

[Loren]

US and Canada cars use the same alarm frequencies (315 MHz).

If the alarm box says "M535" then it is the correct frequency box - but still both could be the wrong version for the car.

[psperl]

Thank you very much for the help guys.

The part number of the both alarm units and DMEs are the same. The alarm unit says M535. However, Durametric does report a different country code and order number for the canadian DME and my original DME. I am not sure if that is important. The order numbers are both '996<something>'.

The air bag unit does show a fault in the driver's belt buckle, but I assume that is because I have the driver's seat removed from the car. Do you think I need to plug the driver's seat back in? I tried this once two weeks ago before I had the Durametric cable and it made no difference, but I hadn't cleared the codes at that time.

Sorry I don't have a screenshot, but I can say that the Durametric shows a green checkmark next to DME unit, a yellow exclamation point (but no fault codes) next to the alarm, and a red error code on the airbag unit for the driver's belt buckle.

About further water damage, I'm not sure where to look. There are no fault codes to investigate. Do they take some time to show up? I feel that the starter relay bridge test rules out the ignition switch, starter, and solenoid. I can read codes and actual values off the DME/Alarm/Airbag units, so its not like the cpus aren't firing up. I'm slightly worried that the canadian units aren't the same as the US units, but then I find it hard to believe that would be the case considering the part numbers are identical.

Do you guys think it is a valid idea to get someone to program my original US DME to bypass the immoblilizer? I read this was possible in another thread on here. If I wasn't at work I would dig it up.

[Loren]

Here is your order type and country code. The only think this might prevent is proper coding of options or changes to options.

Any airbag code needs to be cleared (they will not clear on their own). And, the problem must be fixed to clear the code.

You can not re-program the DME to by-pass the immobilizer (at least not easily).

I would step back and check the simple stuff again.

Clutch switch? (you can bypass it to test)

Do you have a crankshaft sensor signal?

Do you have gas?

[psperl]

Here is your order type and country code. The only think this might prevent is proper coding of options or changes to options.

Any airbag code needs to be cleared (they will not clear on their own). And, the problem must be fixed to clear the code.

You can not re-program the DME to by-pass the immobilizer (at least not easily).

I would step back and check the simple stuff again.

Clutch switch? (you can bypass it to test)

Do you have a crankshaft sensor signal?

Do you have gas?

Thanks Loren.

Clutch switch? (you can bypass it to test) --> I put a multimeter on both sides of the switch, pushed in the pedal and saw connectivity. I will bypass it this weekend.

Do you have a crankshaft sensor signal? --> The engine doesn't even attempt to crank (unless I bridge the starter relay) so is this even a possibility?

Do you have gas? --> Same as the crankshaft sensor signal

Is there something I don't udnerstand? Does the fuel system and crank signal need to be reading some nominal value before the DME signals the starter relay that we are ok to turn over the engine?

Anyway, the one thing I did not try is to plug the seat back in and clear the airbag code for the belt buckle. This implies it is not possible to start the car without driver's seat. Is that right?

Oh man I hope plugging the seat in and clearing the code will make this work, I will have worked myself up over nothing! Thanks again.

-Pete

[coleta]

Loren, what exactly is the order type? If you put it in PET will it give you all the M numbers or something?

[Loren]

Order type is the model "996" and the body type "110" is coupe.

So for MY1999...

996110 = LHD C2 Coupe

996111 = RHD C2 Coupe

996310 = LHD C2 Cabriolet

996311 = RHD C2 Cabriolet

996410 = LHD C4Coupe

996411 = RHD C4 Coupe

996610 = LHD C4 Cabriolet

996611 = RHD C4 Cabriolet

I think you are going to need a shop with a PST or PIWIS to diagnose this one...

[psperl]

Order type is the model "996" and the body type "110" is coupe.

So for MY1999...

996110 = LHD C2 Coupe

996111 = RHD C2 Coupe

996310 = LHD C2 Cabriolet

996311 = RHD C2 Cabriolet

996410 = LHD C4Coupe

996411 = RHD C4 Coupe

996610 = LHD C4 Cabriolet

996611 = RHD C4 Cabriolet

I think you are going to need a shop with a PST or PIWIS to diagnose this one...

Thanks Loren. I'll try to find a private shop in NY that has the right tools. Maybe formula motorsports or sonny's shop if its still around? I'll search around these forums for a respected shop in NYC.

[Richard Hamilton]

I bought the DME, Alarm Unit, and key pill from a (canadian) donor car, so they all match. I can't personally prove that they all match, but the provided key does unlock/lock the doors with the alarm unit installed. My original key pill does nothing, so that seems right.

Conventional wisdom is to get someone with a PIWIS or PTS2 to program the DME to the alarm unit, but I am trying to avoid the dealers. Those guys have done such dirty things to me in the past that I have a hard time going back.

Don't confuse the radio remote with the immobiliser transponder pill. The radio remote will unlock the car, but you will need to transfer the glass immobiliser pill from the donor key head to the old head.

[psperl]

I bought the DME, Alarm Unit, and key pill from a (canadian) donor car, so they all match. I can't personally prove that they all match, but the provided key does unlock/lock the doors with the alarm unit installed. My original key pill does nothing, so that seems right.

Conventional wisdom is to get someone with a PIWIS or PTS2 to program the DME to the alarm unit, but I am trying to avoid the dealers. Those guys have done such dirty things to me in the past that I have a hard time going back.

Don't confuse the radio remote with the immobiliser transponder pill. The radio remote will unlock the car, but you will need to transfer the glass immobiliser pill from the donor key head to the old head.

I did not realize there were two separate components. I do remember seeing some sort of pill, and I think I transferred it. Either way, I will check. Thanks for the tip!

[psperl]

I bought the DME, Alarm Unit, and key pill from a (canadian) donor car, so they all match. I can't personally prove that they all match, but the provided key does unlock/lock the doors with the alarm unit installed. My original key pill does nothing, so that seems right.

Conventional wisdom is to get someone with a PIWIS or PTS2 to program the DME to the alarm unit, but I am trying to avoid the dealers. Those guys have done such dirty things to me in the past that I have a hard time going back.

Don't confuse the radio remote with the immobiliser transponder pill. The radio remote will unlock the car, but you will need to transfer the glass immobiliser pill from the donor key head to the old head.

I did not realize there were two separate components. I do remember seeing some sort of pill, and I think I transferred it. Either way, I will check. Thanks for the tip!

Oh boy do I feel stupid! The best kind of stupid, the kind that doesn't cost me any money! Thanks for the suggestion Richard. I had not transferred the tiny dark glass immobilizer pill. There were no fault codes because everything was fine. I didn't notice that little guy before when I swapped the radio. Thank you so much!

The Canadian brain doesn't seem to have affected the car in any way, so that's good. Now I just need to find and resolve the leak.

I have donated a small amount to show my thanks for this forum. I had maybe two posts before this issue and you guys still gave me sound timely advice. You guys are top notch. Thanks.

[Richard Hamilton]

:thumbup:

[Maz007]

Hi, I need urgent advice please, I have a Porsche Carrera 4 911 996 2001, water has been found underneath seat where control alarm box is situated labelled M535, Part Number: 996.618.262.01, and it is quite serious as the water created an electrical fire that melted control unit. The wires seem slightly corroded and the car will not start. Dash lights illuminate and I have disconnect Control Box. The door has a clicking noise and will not open.

I understand I need to have control box M535 changed that needs to be coded to new key form but curious as to your thoughts to the following:

1) Cost in replacing with new control unit and wiring loom?

2) How far does the wiring loom run if needs full replacement?

Interested in your suggestions and projected cost in fixing the above.

[Maz007]

The damaged wiring:

Edited April 14, 2012 by Maz007

[1schoir]

Maz: I'm not sure about the cost of labor in replacing the immobilizer or the wires running to it, but here's a word of caution that may save you some $$$. IIRC, a new immobilizer can only be programmed once, so make sure that whoever is doing it (with a PST2 or a PIWIS) knows what they are doing. Otherwise you will have to buy yet another immobilizer, and that part is not cheap.

That M535 immobilizer for an '01 996 is part number 99661826203 and lists for about $445.00. You will also need your IPAS codes to program your immobilizer to your keys. You can only get the IPAS codes from the dealer with proof of ownership.

Regards, Maurice.