Remote Key stopped working

[tvacom]

I have a 2000 996 tip, convertable with 79k on it. I replaced the battery in the key but that didnt help. I also noticed that the valet lock will pop on randomly. I had to put it in gear to turn it off so I could pump gas the other day. Any tips?

thanks

dave

[wross996TT]

What exactly is happening? Does the FOB not unlock the car? Does the car start with the key? The remote will automatically disable if left for a week. To restart it, you open the door manually and then hit the key fob button. Other things you can try is to reset the FOB, this is done by putting the battery in reverse polarity for 10 seconds and then installing it correctly. If this does not work, you may need to have the key re-linked to the car. This is done with PST2 or PIWIS.

[tvacom]

the car starts and runs but the FOB wont remotely open the car. I know if it sits you need to open door etc. I will try the reverse polarity and see if that works. . . I wont be with the car until next week. It was working and then one day it wasnt. Do I put a new battery in. . .

thanks

dave

[goldenwarrior1]

You can replace the battery but if no joy then you will need to go to a dealer or someone with a PST2. I had the same problem, did all the usual stuff including battery, switched polarity etc. No joy! Finally took it to the dealer and the remote could not be programmed as it had failed. Ended up replacing the key remote/fob and while I was there had them program a 3rd as a backup spare.

Good luck, Tom

[judgejon]

You can replace the battery but if no joy then you will need to go to a dealer or someone with a PST2. I had the same problem, did all the usual stuff including battery, switched polarity etc. No joy! Finally took it to the dealer and the remote could not be programmed as it had failed. Ended up replacing the key remote/fob and while I was there had them program a 3rd as a backup spare.

Good luck, Tom

you can order the head part from Sunset, and then take it to the dealer for reprogramming. saves a few dollars that way. cheers, jl

[goldenwarrior1]

Our local dealer here in Va Beach matched the price of Sunset and I didn't pay shipping plus on one FOB I brought in a new one that the original owner had given me that he had never got around to programming. Which is part of the reason I ended up with 3 remotes. If all three of these fail I am going to trade the remotes in for a 997 Turbo :rolleyes:

[jayi836]

You can replace the battery but if no joy then you will need to go to a dealer or someone with a PST2. I had the same problem, did all the usual stuff including battery, switched polarity etc. No joy! Finally took it to the dealer and the remote could not be programmed as it had failed. Ended up replacing the key remote/fob and while I was there had them program a 3rd as a backup spare.

Good luck, Tom

Edited January 4, 2011 by jayi836

[jayi836]

What were the cost for the new keys? parts and labor have the same issue with a 99 996 c2

[SA321]

after 3 keys all dying within 2 years I stopped replacing them.

[jpowers]

I was quoted 330.00 with tax for a key for my '02 Targa which has an extra button for the rear hatch.

[dgcook]

Dave:

There is an interesting article in the June 2010 issue of Excellence Magazine entitled: "Fob 4 Less: Fixing a modern Porsche key for less than $3 bucks". The article describes rescuing a dysfunctional key by replacing a couple of small, inexpensive momentary switches. Looks relatively easy to do and since the electronic functions of your key are already messed up you don't have much to lose. I have one non-functional fob, but since the other is working I haven't tried this idea yet. I did call the dealer about a replacment. They offered to solve the problem for $375. If you go the diy route please let folks know how it works out.

Good luck.

Dave

[waliboy]

Hi Dave

do you know the part number for the momentary switches? I'm in the UK and we don't see Excellence Magazine over here.

W

[dgcook]

Waliboy:

The article lists the source for the momentary switch as: www.digikey.com, phone # (800-344-4539). The three switches are normally off (part # CKN9193CT-ND). The web link is:

http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=US&WT.z_homepage_link=hp_go_button&KeyWords=CKN9193CT-ND&x=27&y=19

If you need further information let me know.

Good luck.

Dave

[waliboy]

Hi Dave,

many thanks for the info. Do you know who makes the battery holder? The number on the reverse side is 70105003 (see pic)

W

[kbrandsma]

Dave:

There is an interesting article in the June 2010 issue of Excellence Magazine entitled: "Fob 4 Less: Fixing a modern Porsche key for less than $3 bucks". The article describes rescuing a dysfunctional key by replacing a couple of small, inexpensive momentary switches. Looks relatively easy to do and since the electronic functions of your key are already messed up you don't have much to lose. I have one non-functional fob, but since the other is working I haven't tried this idea yet. I did call the dealer about a replacment. They offered to solve the problem for $375. If you go the diy route please let folks know how it works out.

Good luck.

Dave

Hi Dave,

Would it be possible to borrow your copy of Excellence. I'm in Everett and would be more than willing to pay postage bothways or catch up with you sometime. I go to Bellevue, once a week or so..

Regards, KBrandsma

[mattatk]

Not too much to the job. I am truly an amateur & still managed to fix the fob.

eBay or the above link for the microswitches. Get a cheap small soldering iron. Plier off the old switch, making sure you note where it came off the circuit board. Solder on new switch.

Hopefully, job done!

[dgcook]

Waliboy:

The article doesn't mention replacement of the battery holder. Their theme seemed to be that the micro switches are the main culprit behind fob failure and hence focus on that. I have ordered some switches to try and fix one of my own poorly working fobs. In the process tinkering with mine I'll give your question more thought.

Dave

Hi Dave,

many thanks for the info. Do you know who makes the battery holder? The number on the reverse side is 70105003 (see pic)

W

[waliboy]

Hi Dave,

changed one of my microswitches - the one that operates the alarm/central locking and it wasn't a success. The replacement is quite easy and I made sure that the switch is clear of the circuit board. I'll be replacing the battery holder next, if I can find a suitable replacement. Let me know how you get on.

I can't help thinking that the fault may lie elsewhere. The battery is outputting over 3 volts and the microswitch is closing contact and the little red light flashes as it should but there's no unlocking of doors, no unsetting of the alarm. What surprises me is that the other button that operates the luggage compartment seems to be OK. Is this a separate circuit? Are there two aerials? I can't think of any reason why there should be. Any observations appreciated.

W

[dgcook]

Waliboy:

Are there any indications that the other switches may also be faulty? Since they are "momentary on" this means if you place a volt meter at either pole, activating the switch should send the voltage drop across the switch to zero--an indication the switch works. The info you provide suggests the switch probably does work, but this is still a good way to insure. Short of that I am wondering if there is a way to obtain a circuit diagram to attempt proper diagnostics ?

Dave

Hi Dave,

changed one of my microswitches - the one that operates the alarm/central locking and it wasn't a success. The replacement is quite easy and I made sure that the switch is clear of the circuit board. I'll be replacing the battery holder next, if I can find a suitable replacement. Let me know how you get on.

I can't help thinking that the fault may lie elsewhere. The battery is outputting over 3 volts and the microswitch is closing contact and the little red light flashes as it should but there's no unlocking of doors, no unsetting of the alarm. What surprises me is that the other button that operates the luggage compartment seems to be OK. Is this a separate circuit? Are there two aerials? I can't think of any reason why there should be. Any observations appreciated.

W

[waliboy]

Hi Dave,

tested the removed switch and the unused replacement switch. Both are working the same way, i.e. when pressed they close the contact.

Tested the remote on a proprietary remote tester at my friendly Porsche specialist, unfortunately forgot to get the name of the tester. The tester flashes when it sees a signal being sent and it shows a signal is being sent from both of my remotes. Next step is to see if the aerial mod suggested on this forum improves the signal reception.

I don't know of anybody who has a circuit diagram.

W

[dgcook]

W:

I saw the aerial mod DIY you referred to. It's interesting, but there were a couple of places where things seemed a bit unclear to me. Please report back on how that goes and any additional information that may be helpful to others who might try the same thing.

thanks

Dave

Hi Dave,

tested the removed switch and the unused replacement switch. Both are working the same way, i.e. when pressed they close the contact.

Tested the remote on a proprietary remote tester at my friendly Porsche specialist, unfortunately forgot to get the name of the tester. The tester flashes when it sees a signal being sent and it shows a signal is being sent from both of my remotes. Next step is to see if the aerial mod suggested on this forum improves the signal reception.

I don't know of anybody who has a circuit diagram.

W

[waliboy]

The story so far:

MY2001 Carrera II manual UK model. 2 button key fob stopped opening the doors and unsetting the alarm using one of the buttons but the other button that opens the luggage compartment and unsets the alarm works fine. Tried the following:

1 Replaced the battery after checking the voltage

2 Tried the "bit of card" trick. This is to increase the pressure of the battery against the terminals in the battery holder

3 Tried turning the battery round (this appears to short the negative and positive terminals of the battery holder together). Presumably this is to discharge the chip

4 Tried putting the key in the ignition, turning the ignition on off and then removing the key and pressing the button to reset the rolling code

5 Checked all solder joints and remade any that looked suspect

6 Replaced the switch on one of the fobs. The replacement switch is slightly taller and seems to catch in the fob case so I might swap back

7 Checked the aerial/antenna length and found it to be 95 mm. The frequency here in the UK is 433 MHz which apparently needs a length of 165 mm.

8 Extended the length of the antenna to 165 mm

The key works occasionally which leads me to believe that it does not need reprogramming. I've tried it from a few feet away and from 20 feet away just in case it disregards too strong signals (can sometimes happen with infrared). Got my radio frequency scanner and checked the area around 433 MHz and didn't find any spurious signals coming from other local devices. When I operate the fob I see that it's not always the same frequency. Does this device employ frequency hopping as well as rolling code?

Have I missed anything? At what point does the ground plane for the antenna earth? My old 928 used to have an occasional problem with the earthing points and I thought I'd give the appropriate one a clean although I don't have any other problems apart from the cigarette lighter does not work (checked the fuse and that's OK). Does this share an earth? Should I try and aerial with a local ground plane? Should I try using a separate power supply that delivers 3 volts just in case there's a lot of internal resistance?

Any ideas welcome!

W

[barlowdo]

Any luck with this? Is the internal clock chip or whatever is used to create the carrier frequency failing which is giving you the changing frequencies?

[thirteeneast]

Hi Waliboy, I also have a key that now does not work.

My key can clearly be seen on my RF Spectrum field strenth meter but I think mine has lost its code so therefore will not work at all.

Strange that yours is intermitant.

P.s those microswitches are all over ebay or Maplins,Farnel/Cpc etc

Edited June 27, 2012 by thirteeneast