996 TT Key fob and fuel door
 

Hello, I am the new owner of a 996TT, 2004. I have two issues, and am wondering if they are related.

1. The key (the only one I have) works in the ignition and door, but does not activate neither the trunk release nor the keyless lock/unlock feature of the FOB. It does flash red when pressing the buttons, but does not seem to be communicating with the car.

2. My fuel door won't open.

Could these two issues be related? Thanks in advance for any suggestions.

The key fob the circuit board in the fob plays no role in starting the engine. There is an RFID pill (small glass enclosed capsule) that receives an energizing RF transmission from the car's security system -- the antenna is behind the ignition key surround -- and then turns around and transmits its ID. If the security system recognizes the ID the engine is allowed to start, well, crank at any rate.

That the door locks react to the key fob button press says the circuit board is at least partially working. That the trunk release isn't working could be due to several things.

I have found in the past that for a wonky fob that removing the battery and reversing it then removing it and installing is the right way can resurrect the key fob circuit.

In at least one case I used a dead key as a donor for a switch -- under one of the buttons -- and had a tech at work unsolder the donor switch and then the suspected bad switch and solder on the donor switch to the otherwise working fob and the button worked again.

The fuel door could be due to a problem with the locking pin which is worked by a solenoid. I never experienced any problem with this with my Turbo but early on in my Boxster experience I found the fuel door was not locking. I figured out this was due to a missing plastic bushing that slides over the locking pin and snaps into a hole in the metal basin. Earlier I had found this bushing loose and in the basin but didn't realize where it came from. Fortunately I saved the bushing and then when I found the fuel door not locking with the fuel door open I worked the door lock/unlock button and saw the locking pin make some attempt to move out but it was just a fraction of the distance required. I noticed the pin had a pretty large hole through which it was to extend out to engage the fuel door. It was then the purpose of the plastic bushing became clear. I installed the bushing and then working the lock/unlock button the locking pin extended a good distance out and engaged the fuel door and locked it.

'course, with the lid locked how can you open it and even look things over? There are emergency releases for the two trunks. But I can't recall if there is an emergency release for the fuel door.

Another little know fact... If you activate the keyfob while out of range to the car (like siting on it in your pocket), the fob will be deactivated after 256 attempts (a few seconds of pushing the button). To re-initialize, simply put the key into the ignition and turn on and off. After 1024 activations, you fob is toast and even the dealer can never bring it back to life.

Another issues I have found is that the micro-switches on the circuit board can break pretty easily. I have one that is shot on my "second" key. Still trying a way to fix it that does not involve micro level soldering (which I am not good at, come to think of it I am not good at soldering anyway...).

I've had that issue with the fuel door. My fob remote has never worked, but I've unlocked the fuel door by locking and unlocking the car manually. Be aware, you have about 20 seconds to get the key in the ignition or the alarm will sound.

Your alarm should NOT sound when you unlock the door with the key - something is wrong.

It is one wired to the front of the pass. side door opening on my '02

Good call - I've never noticed that... I'll have to have a look...

My experience is if the car was locked using the key and the door lock button if one unlocked the door with the key blade he had around 10 seconds to insert the key in the ignition and turn the key to the on position otherwise the alarm would sound.

I encountered with with both my Turbo and Boxster once in a great while when I tried to unlock the door with the key button but for some reason this didn't work and I had to resort to using the key blade to unlock the door.

Yeah, since my FOB has been toast, I use the key all the time - there is never a time-limit to start the car (or there shouldn't be).

RTFM...
https://cimg6.ibsrv.net/gimg/www.6sp...c5cc8d0c4a.jpg

... and where did that come from? (It's not in my manual)

from 2003TT manual, page 21. So this may not apply to you, but it does to the OP