Porsche 996 - Alarm specialist in Medway//Kent?
Porsche 996 - Alarm specialist in Medway//Kent?
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Discussion

LotusAlfaV6bloke

Original Poster:

203 posts

215 months

Monday 13th June 2022
quotequote all
I have an issue with the alarm on my 996 C2 (2002 manual).

When I go to lock it I get the "double beep of doom" and it locks and then immediately unlocks straight away. Unlike the single beep warning (meaning something isn't closed fully), this actually means something is broken/failed with the alarm system.

My Autel scanner has pulled these codes from the alarm module:
33 - Passenger Compartment Monitoring
59 - Central Locking Limit Position. Secure not reached.
54 - Radio Receiver Faulty

I have owned the cars 8 years, and have made no recent changes of any kind, and I understand that the code 54 for the radio is a pretty standard code to get for anything aftermarket that is fitted (which my car has had ever since I had it). My scanner will read the codes above but when I try to clear them it refuses to, not sure why. The alarm module under the seat is clean, dry, and undamaged and passes a visual inspection.

I have replaced the cabin motion detector as I thought this was the issue based on the codes, but the alarm still has the same problem and fault codes after the new one is in place.

I do not have Durametric and I have taken it as far as I can with door handles and boot/lid glovebox, and centre compartment switches all seemingly functioning.

I am in Medway (Kent) - any suggestions who can I take it too? Please help!

allatsea

144 posts

168 months

Monday 13th June 2022
quotequote all
LotusAlfaV6bloke said:
I have an issue with the alarm on my 996 C2 (2002 manual).

When I go to lock it I get the "double beep of doom" and it locks and then immediately unlocks straight away. Unlike the single beep warning (meaning something isn't closed fully), this actually means something is broken/failed with the alarm system.

My Autel scanner has pulled these codes from the alarm module:
33 - Passenger Compartment Monitoring
59 - Central Locking Limit Position. Secure not reached.
54 - Radio Receiver Faulty

I have owned the cars 8 years, and have made no recent changes of any kind, and I understand that the code 54 for the radio is a pretty standard code to get for anything aftermarket that is fitted (which my car has had ever since I had it). My scanner will read the codes above but when I try to clear them it refuses to, not sure why. The alarm module under the seat is clean, dry, and undamaged and passes a visual inspection.

I have replaced the cabin motion detector as I thought this was the issue based on the codes, but the alarm still has the same problem and fault codes after the new one is in place.

I do not have Durametric and I have taken it as far as I can with door handles and boot/lid glovebox, and centre compartment switches all seemingly functioning.

I am in Medway (Kent) - any suggestions who can I take it too? Please help!
I'm sorry I can't help, but I have exactly the same issue on my 1999 C4, and have done broadly since I brought it in Oct 2021. However, tonight mine has taken a turn for the worst and started to alarm 30 seconds after the double beep.

Only difference is mine stayed locked after the double beep.

Like yours, under the passenger seat is bone dry, obviously never seen water, changed the motion sensor (twice), passenger door lock, tilt sensor and had my indie look at it without success. I ended up just putting up with it.

It started alarming, as it is tonight, a couple of months ago, Indie managed to reset and appeared sorted, then tonight started doing it again.......

Will watch this thread and hope someone knows the answer.....

Pope

2,653 posts

270 months

Tuesday 14th June 2022
quotequote all
The door locks have multiple microswitches that report positions of the lock mechanism to the alarm ecu:

- Door Open/Closed
- Lock Locked/Unlocked
- Deadlock(safelock) Engaged/Disengaged

The locks are synchronised; if one shows locked/deadlocked then the other should too - a mixed report is implausible = double beep

The timing of the double beep is important; if it double beeps as you lock the car it is reporting a different issue to a double beep when you unlock the car.

The issue is usually a short circuit on the PCB within the lock assembly - the tracks run very close together and moisture gets into / onto the board and corrosion 'joins' the tracks resulting in faults. You CAN repair them - scrape away the protective coating in the affected area thereby removing the corrosion and apply some sealant to reproof the tracks, this staves off the worst and gives a few more years use - a replacement lock is quicker but more expensive......

Get the car on a tester; view the actual values and check which lock is reporting implausible, ie: it says its locked / deadlocked when it isn't and that'll be the culprit

Hope this helps!

Edited by Pope on Tuesday 14th June 00:47

julian987R

6,840 posts

82 months

Tuesday 14th June 2022
quotequote all
LotusAlfaV6bloke said:
I am in Medway (Kent) - any suggestions who can I take it too? Please help!
https://www.eliteporsche.co.uk/2021/12/21/porsche-996-turbo-alarm-fault/

Belvedere in Kent

allatsea

144 posts

168 months

Tuesday 14th June 2022
quotequote all
Pope said:
The door locks have multiple microswitches that report positions of the lock mechanism to the alarm ecu:

- Door Open/Closed
- Lock Locked/Unlocked
- Deadlock(safelock) Engaged/Disengaged

The locks are synchronised; if one shows locked/deadlocked then the other should too - a mixed report is implausible = double beep

The timing of the double beep is important; if it double beeps as you lock the car it is reporting a different issue to a double beep when you unlock the car.

The issue is usually a short circuit on the PCB within the lock assembly - the tracks run very close together and moisture gets into / onto the board and corrosion 'joins' the tracks resulting in faults. You CAN repair them - scrape away the protective coating in the affected area thereby removing the corrosion and apply some sealant to reproof the tracks, this staves off the worst and gives a few more years use - a replacement lock is quicker but more expensive......

Get the car on a tester; view the actual values and check which lock is reporting implausible, ie: it says its locked / deadlocked when it isn't and that'll be the culprit

Hope this helps!

Edited by Pope on Tuesday 14th June 00:47
Not trying to hijack, sorry OP!

Thanks Pope, this is why the passenger door lock was changed, but clearly still have an issue. Next stop drivers door lock. On the plus side have 'reset' the alarm this morning (after a night with the battery disengaged) triple locked, unlock the door with the key (have I made this up?) and now, just back to the double beep on locking, no alarm 30 seconds later.

Going to the Indie today to pick up my 986, so will have another chat with them about it.