So my 981 has a few wierd things going on. I think I will rename it the Blue Ghost. A couple of months ago, whenever I lock the doors with key fob, and walk away, the alarm goes off. So I booked an appointment at my local Porsche Dealer, to take a look at it, and they want the car for 1+ days to diagnose. They obviously won't take the warranty I purchased because I did not buy the car there, (WHICH I THINK IS A LOAD OF BS) which means I will pay out of pocket and hopefully get reimbursed, but it is a hassle. What really bugs me is that I am not keen on paying $300 an hour for a whole day's worth of labor to diagnose, if it takes that long.

The only things i have done since i bought the car, is install the Isudar wireless board into the PCCM, Changed the low beam and high beams to better and brighter bulbs, install led bulbs in all of the interior and trunk spaces and mounted a light bar on the tail, which was plug and play. I have not altered any wiring in the car, other than installing the Ambient Light Packahe with all genuine porsche parts and harness, and that was installed after I started having issues with the alarm.

Any ideas on what might be wrong? I did not get any errors after changing the d3s low beams or H7 High beams or side marker lights.

I think you saw the posts where another user had their alarm go off after replacing the headlights with LEDs. I don't believe they had PCM errors either. Edit: it had something to do with the LED fans drawing power even when the lights were switched off, if I remember correctly.

Before paying Porsche to diagnose, switching back to the OEMs seems like a very easy troubleshooting for you to try. If you switch back to the old lamps and no alarm, you have your answer. If not, you look at the next thing.

This.

Start unwinding all your electrical modifications (that IS a lot) one at a time and test for a few days to see what is causing the miscommunication. Something you changed or added is clearly not playing nice with the OE computers.

Found the earlier thread

Is this your issue also?

[QUOTE=ShiftyWolf;19849601]I think you saw the posts where another user had their alarm go off after replacing the headlights with LEDs. I don't believe they had PCM errors either. Edit: it had something to do with the LED fans drawing power even when the lights were switched off, if I remember correctly.

I did see those posts and did think of that. I did replace the existing D3s low beam with a newer brighter D3s, and did not change any wiring or add any ballasts. But on the highbeam, I did replace the H7 with HID H7. Again, no ballast or wiring changes. If I had to guess that that was the cause.I think I should look at the high beam first not the low beam. But isn't that kind of stupid to tie the freaking light bulbs to the alarm system? Hey, you know what? I think instead of stealing the car, I'll just steal the light bulbs and make the Is car alarm go off. Wondering if there's a way to coat it to accept the bulbs that are there and maybe stop the trouble.

Let me clarify that. Low beam D3s just changed out the bulb to brighter and more lumens. Morimoto XB, no additional wiring and no fans. The highbeams, H7 were swapped out with LasFit H7 LED fanless. Again, everything plug n play, no ballasts or wiring changes. I was worried that choosing one with fan wouldn't fit in the cavity. I also swapped out the side marker lights with LED as well. So I think the highbeams are the culprit and going to test that theory. But also wondering if they can be coded if that turns out to be true. Looking gor the other thread on this subject and having trouble locating it.

Thanks for the replies

Let me clarify that. Low beam D3s just changed out the bulb to brighter and more lumens. Morimoto XB, no additional wiring and no fans. The highbeams, H7 were swapped out with LasFit H7 LED fanless. Again, everything plug n play, no ballasts or wiring changes. I was worried that choosing one with fan wouldn't fit in the cavity. I also swapped out the side marker lights with LED as well. So I think the highbeams are the culprit and going to test that theory. But also wondering if they can be coded if that turns out to be true. Looking gor the other thread on this subject and having trouble locating it.

Thanks for the replies

I FOUND IT. Thanks for the link posted earlier here. There is a way to code it out. Sweet Mary Jane!

for anyone else having this issue, my friend just had this exact problem in his 2013 991.1 carrera s. there are 2 main causes of this problem, and it happens pretty much across the entire porsche lineup (cayenne's, boxsters/caymans, 911's, and panamera's) the first cause is when people replace the high beam H7 halogen bulbs with H7 LED's that have a fan. if you want to replace your high beam bulbs with LEDs you have to get the fanless LEDs because the fans trigger the alarm specifically when installed in the high beams. You can easily diagnose this because when the high beam bulbs cause this issue, the high beams will flash right before the alarm goes off (which doesn't normally happen when the alarm is activated). This will happen about 1 or 2 minutes after you get out and lock the car and will happen every time you lock the car.

If you didn't replace your high beams with LEDs and are having this issue, the second known cause of this problem is the alarm siren module failing. When the siren is the reason though, it causes the lights to flash randomly after locking the car. It could be 5 minutes after locking the car or 15 minutes after, and is mainly starting to happen in cars over 10 years old. The battery inside the siren is not replaceable, and with age it begins leaking on the circuit board which causes this issue. It will also drain your cars battery if not addressed immediately so right after you diagnose this issue being caused by the alarm siren, you need to pull the fuse for the alarm siren. Pulling the fuse will stop the battery drain and gives you time to replace the alarm siren. Also, try not to replace with a used siren because you will just be kicking the can down the road, if you do get a used one make sure it is no more than 2-3 years old which should give you 7-8 years of usable life before it fails again(hopefully). The good news is they are not too crazy expensive from the porsche dealership, around $266(latest part number is PAB951605). Another option is getting chinese ones from amazon, i found one specifically with 5-star reviews and both reviews stating that they installed them in 2 different porsche models, and they both said it worked perfectly. They are only $93, and this is what my friend ordered. I will update this post after install if the cheap amazon one causes any issues.

Great information. Thank you. I thought the dealer checked the siren battery, but to be honest, They didn't even know how to code out the headlight monitoring That is causing the alarm to go off because of the headlight issue so I have to figure that out myself, so I am not sure. On another note i'm not sure that the hi beam l a d issue is connected to a fan or not. In my 981 I was afraid that an LED high beam with the fan wouldn't fit because this cavity that it goes in is very small so I used a Fanless LED H7 and it's still causing the alarm to go off.

One question though, where is the siren battery located so I can check it?

The battery is sealed inside the siren assembly and can't be easily inspected or replaced. I don't think anyone has disassembled the siren assembly without damaging the housing.

Not all cars seem to have this siren module, from what I've read; some apparently have a more conventional horn that has no backup battery.

what @Larson E. Rapp said is correct, but if your still having the issue and have chinese LED's installed, fan or not first thing you need to do is remove those. I know some fanless LED's work but not sure about all, with those cheap LED's you never know but is definitely easy place to start, especially since we know for sure the LED's with fans definitely cause the issue.

I'm going the coding out option as soon as the weather gets warm. I like the bulbs too much to change out. I am told that you have to a cess the front body module in developer mode and code the alarm monitoring to ignore the headlights. Problem fixed I hope. What I find really nutty or actually very stupid, is why Porsche would want the alarm system to monitor the headlights in the first place. If I am a thief, and I can get into the car to pop the frank to access the headlight removal tool, why on earth would I waste time stealing the headlight bulbs, but leaving the rest of the car there???

I can actually see some people digging that look. If Tesla had shipped cars from the factory that looked like that, they would have a cult following.