Central Locking Issue 2004 996TT Cabrio

[flyingchef47]

Recently acquired a very nice 2004 996TT Cabriolet. I only drive it on weekends and can go for several weeks without driving. Prior owner had a trickle charger installed so hooked that up on my last trip away. Upon returning home I used the key to physically unlock the car and went out for drive only to find that when I went to park the car the remote would not work to lock the doors nor would it open luggage compartment (frunk). Also, found the buttons at door sill do not unlock the luggage compartment nor engine lid. Started engine and engine lid button worked, but button will not open luggage compartment. 

 

Tried the “clear load switch-off” method of unlocking door and pressing remote, but no success.

 

Tried both keys which light-up as if they are emitting as normal, so doubt the key fob is an issue. Looked at many posts but have not seen any reference to anyone else with same problem.

 

The alarm system was not active upon purchase of car so never had any beeps or honks, so no insights from that system to learn from.

 

Thanks to all for any help.

 

Mark

Edited March 17, 2018 by flyingchef47

[Loren]

After 5 days the alarm system shuts down remote activation to save the battery. It is normal to have to unlock the car with a key after that 5 days.

 

You should not hear beeps from the alarm system when arming or disarming.

If you did have beeps then - one beep means one or more alarm zone(s) are open.  Two beeps indicate there is an alarm fault that needs to be corrected. I would suggest cleaning both remotes and installing a new battery in each. Then give it a try.

[flyingchef47]

Loren,

 

Thanks for the response. I replaced the batteries in both keys and then tried to reactivate the remote communication, but still nothing.

 

Dashboard button for locking doors and the engine lid release at the driver’s door sill work fine with engine running. But the luggage compartment will not pop under any circumstance and remote door locks do not work. Lights flash on keys, but no response from car.

Edited March 18, 2018 by flyingchef47

[Loren]

Check and or replace fuse E1 (7.5A).

[flyingchef47]

Thanks - will do. Just headed out for a two week business trip so will update upon my return. Many thanks.

Mark

 

[flyingchef47]

Loren,

 

Just got home to Atlanta this evening and checked fuse in slot E1, but it’s fine.

 

Any other thoughts?

 

thx,

mark

[Loren]

Any chance the control unit got wet? (it's under the drivers seat)

[flyingchef47]

No, not at all. I’ve only driven the car in dry conditions, and it’s been stored unde cover in a garage since I acquired it in January.

 

Mark

[Loren]

Hmm... you will likely need to use Durametric or Porsche PIWIS to see if there are alarm/lock control faults.

[flyingchef47]

Yeah, I kinda thought that might be next step.

 

thx,

Mark

[flyingchef47]

Update To All,

 

Finally took the TT to my local Porsche dealer who hooked it up to their PIWIS. Issue was found to be a small 5 amp fuse found INSIDE the immobilizer box (under the driver seat) that was blown. Mechanic said that it may have been related to a small bit of age related corrosion on one of the circuit board connections that he was able to scrub off, but suggested to keep an eye on it in case it should happen again.

 

All is back in order and working fine.