key fob re-programme

[jramsden68]

I spoke to the OPC about a key fob that had stopped working. The answer was to purchase the inner electonic portion of the key fob and then programme the car to receive the new key. The programming of the car has to be done via the connection of their diagnostic equipment. Apparently the car can receive signals from any number of key fobs, providing the signal sequence from the key fobs are programmed into the car.

However, there appears to be an ebay sale where the seller states that there is an alternative manual method, without the need for using the OPC. The seller states that a series of key presses can re-synchronise the key fob to the car. Has anyone heard of such a method for the Porsche? [I know this method works for BMWs].

The advert on ebay is: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ih=013&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=230092867765&rd=1&rd=1

Thanks, Jason

PS: I know there is a signal from the key fob, as I have tested it on a spectrum analyser. It is possible that the processor in the key fob has "lost" the sequence, although the RF transmission portion is still working. If this is the case, then there is not choice but to purchase a new inner portion via OPC.

 

[Mark_Bennett]

It says

"Covers Porsche 911 with pop-out style key"

Are there any?

 

[pwafer]

Looks like a load of twaddle to me.

The keyfobs use a 433Mhz rolling code system, similar to your garage door openers... HOWEVER... like all modern cars, the ECU needs to learn any new remote codes using the OPC main computer while connected to your car. Otherwise, it would be a car thieves dream purchase for £2.99 +p&p.

I'd bite the bullet and get the OPC to do it. How much are they want btw? Audi wanted 2 hours labour, so including the key it worked out at £140 !!!!! [8|]

At least you don't drive a Fiat Brava/o, they used to come with a master re-programming red key, that if you lost, you needed to buy a new ECU at over a grand!

[]

 

[jramsden68]

ok, thanks guys .... thought it was a load of twaddle, but just had to get another opinion. Will purchase another electronic portion of the fob & get it coded to the car. Think its something like £70 parts and £50 labour + VAT, so not too bad.

Strange thing is that I checked both key fobs, and they were both at 433 MHz. Also on zero span, they both gave out what seemed like random codes. Just one of them wont open the door. [8|]

Cheers, Jason []

 

[Richard_Hamilton]

Have you tried resetting the remote? Put the battery in the wrong way round, remove it, and then put it back in. Here is an extract from the TSB:
2. Restarting the processor: 2.1 Remove battery2.2 Insert battery briefly with polarity reversed.2.2.1 After a waiting time of at least 10 seconds, slide battery with the polarity of the batteryreversed (positive terminal downwards) under the tab.2.2.2 Clip battery downward into the holder.2.2.3 After a waiting time of approx. 3 seconds, remove this incorrectly polarized battery again.2.3 Install battery with the correct polarity.2.4 Check the function of the remote control. email me if you want complete details. There is a limit of four remotes that can be programmed to the car, BTW.

 

[Paul Fraser]

Have a look on Boxa.net. There is a thread about Timpsons supplying replacement keys for £30 that will open the car and work with the immobiliser but not do the central locking.
http://www.boxa.net/forum/index.php?showtopic=26319&hl=

 

[pwafer]

ORIGINAL: jramsde1
Strange thing is that I checked both key fobs, and they were both at 433 MHz. Also on zero span, they both gave out what seemed like random codes. Just one of them wont open the door. [8|]

Cheers, Jason []

433MHz is just the carrier frequency, most car remote systems use 433. I used to have a SAAB and when you pressed the unlock button, no one else could open their cars in the car park []
My company use the same frequency (but 433.9MHz) for a lighting system... rakocontrols.com

 

[jramsden68]

pwafer .... meant to really say that both key fobs appear to be transmitting the same ... ie same power on same frequency. So RF side looks ok. It could be that the embedded signal within the main carrier is corrupt somehow.

Richard .... sent you a separate email. I will give the reverse polarity method a go.

Thanks, Jason

 

[jramsden68]

Tried the "reverse polarity" method ..... unfortunately no success. Looks like a new innner fob ... Jason