Key fob remote signal not being recognized

Last week my car stopped recognizing the signal from my key. When I press either remote button on the key, the red light on the key flashes but the red light on the dashboard by the windshield doesn't flash. In the past when this has happened, I've been able to fix the problem by using the reset procedure discussed in the archives of putting the key in the door and then turning the key while pressing the door lock/unlock remote button on the key (which causes the red light on the dashboard by the windshield to flash as well). Now the reset procedure isn't working. The red light on the dashboard by the windshield doesn't flash when I'm turning the key while pressing the door lock/unlock remote button. I've replaced the key fob battery but the problem persists. Any ideas for a fix?

New key, $400 from dealer..Sorry

I had exactly the same problem earlier this year. Took it to the dealer for troubleshooting. C4CRNA is correct. You need new keys. The circuit board in the key apparently fails after a period of time (in my case 10 years).

Even though the LED blinks the key head has probably failed. You can get one (or two) from Sunset Porsche for less then $100 ea. Then you will have to take it to a dealer to have it (them) programmed, ~$125. If you get one from E-bay or a non-dealer source make sure that it has the code attached or it cannot be programmed. If you lose the blade it will cost ~$200+ to get one cut.

yikes.

Could of sworn I already replied to this problem. Anyway here is something else I have found. One of my keys did not seem to operate properly. I was being a little heavy handed keeping my thumb pressed on the button. Now I find if I do a quick tap of the key button the system works flawlessly. If I press for any type of extended period of time like over a second I'll end up doing something like looking at the keys diode light flash wondering why things aren't working. Now I just do a quick jab of the button and get a funny feeling about the last 2 weeks of remorsing about the litle keys function. Try a quick jab at the button. My always good key doesn't care how long I press the button and will open and lock the car being heavy handed. Then there is as I could of sworn I mentioned previously. Capacitors are normally the culprit due to they dry out. I'm lucky to be a ham radio operator so working on components wouldn't scare me lke dealing with swapping out the surface mount capacitors which could be a quick painless solution.

Your Key is Dead, i am in the same Situation... My Service Advisor told me this Thursday that my Key is Dead and will need a new Key Head... You just need a new Key Head... Make sure when you do get a New or a Used Key Head, it comes with the Programing Code that looks like a Bar Code, without this you wont be able to have it Programed via the Dealer... Its not $400 as some people here say, they just talk have no idea what they are talking about (As Usual)... New Key Head is $125 from Suncoast http://www.e-partssales.com/miva/mer...y_Code=996keys I think the Retail at your local dealer should be about $150... Programing should be about $50-60... You just have to Swap the Key Blade to the new one, and your good to go for about $200... Good luck

Zookie, the $400 +/- price is if someone has lost their key or only had one key and they want to buy a spare key. Then they have the expense you mentioned above PLUS the added expense of getting a blank key blade and have the key blade cut to match the car.

Local dealer here charges over $200 for a key head, about $22 for a key blade, and additional to cut/synch to the car, just had this done recently... When you press the button, does the light on the key head blink slower than normal? That is an indication of the remote going out of synch w/the car, and this cannot be remedied without the programming ID card of the key. If you buy a new key, try to save this in case you need programming again.

To Pac996, Would you mind sharing what is the location of the capacitors that you've replaced? I am trying to do some fixing before buying a new key. thx, smak

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I haven't replaced any capacitors. My intenet seaching for a schematic was fruitless. I'll keep looking once in a while and hopefully find the schematic some day. Currently I am able to operate the fob by using a quick tap of the button instead of a steady depression of the button. If your led light does still light like my faulty fob does then try doing the quickest tap of the button to get a flash of the led to happen. This is the current way my bad fob will operate. The system does require the key to be right next to the door. I am uncertain of where the receivers antenna is for this system.

I have no luck with the schematic neither. I will try the " quick tap " method. If it doesn't work, I probably will try to resolder the 2 battery Pin through hole connection. We'll see how it goes.

Has anyone found a schematic or had success with swapping any components on a FOB to bring it back to life? (besides the micro switches)

Any ideas for a fix? If you can get in, try putting the key in the ignition,(don't turn the key) then press the key button on the fob

It would be nice if someone found method to read the unique key ID from the chip on the Fob thus allowing for a reprogram via PIWIS.

Was doing some research on my same issue and came about this thread. Just though I'd post that, after having mine work very intermittently recently (worked 25% of the time?), I took it apart, pulled the battery, unsoldered the battery case, retouched all the solder joints with just tiny bit of flux and solder, and now it's back to working beautifully again. Took about 5 minutes. (Note that I'm an experienced solderer and have a fine tip on my iron for small parts like that.). I bet this is the problem with most of them.

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This can be done...

Tried everything and did the reverse polarity last and it worked. my fob is beat to craps but it's still ticking.

Call these guys and see if they can help if it acts up again. They just rebuilt a key fob on my 993 while they were rebuilding my immobilizer. Looks like they work on 996s too. http://www.ecudoctors.com/porsche-996-2000-2004.html

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These are RF transmitters. In my professional photography work I use them to trigger remote flashes. What I learned is that the radios are very sensitive to the battery voltage. Be sure to try a brand new fresh battery. In my case, the battery showed almost 3V on a meter, and flashed the little LEDs in the key fob but would not trigger the radio. When I replaced it with a new one, everything worked. Good luck.

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I've never seen anyone post info regarding recovering the 24 digit code (any fashion or via PIWIS) that comes on the original key head.

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PST1/2/PIWIS I/II/III all display a portion of the code to identify the remotes, I did read once someone found the entire hex code but didn't look into it any further but I am curious about it.

So, I have a 997.1 TT (2007) with PCM, Sport Chrono and Tiptronic (who knows, that may matter for this subject). Saturday morning I went to garage to head out for a drive and the key remote would not open the door. I had driven it less than a week prior to this so I knew it was not in hibernation mode. So, I unlocked the door manually, put the key in and turned it to disable the alarm. Then took key out, shut the door from outside and it still did not lock/unlock the door. Thus, changed the battery. Still nothing. Red LED on key fob was working before new battery and after. Maybe the battery I replaced was bad, maybe not as the LED does not take much power as has been said. The day before I had key in my pocket all day and with what I was doing probably caused the buttons to be pressed a lot and maybe stay pressed (we all are familiar, I am sure, with sitting down with 997.1 key in your pocket and your front lid pops open). By the way, the key would start the car. Anyway, I went and got the other key and it would unlock and lock the car so I knew it was the key. Enough of that for the time being, I went on my drive bringing the extra key with me. Last night I did some research and found this post and some others. I did everything on https://rennlist.com/how-tos/a/porsc...working-377643 and nothing, ideas from other posts too. I tried pressing the buttons with key next to door key slot as the manual suggests. I also put the key in the door, held the button and unlocked and locked. Nothing worked. Today I got in the car and tried the re-sync (step 3 in link above). That did not work. I closed the door and this time I put the key in (I cannot remember if I was holding the button down when I put the key in or after I put it in). With the button pressed, I turned the key to the first stage to turn on the instrument cluster and let key come back. I never let go of the button and held it for 10 to 20 seconds. I do not recall any light on the dash illuminating. After that I pulled the key out and pressed the button. The door locked! I unlocked it with the remote, locked and unlocked it again then got out and locked/unlocked again. The remote was again working as it should. Hallelujah! I did not find the process I stumbled across that worked for me written anywhere so figured I needed to create an account and post this. Hope it helps someone sometime. Cheers!

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I had a very similar experience with my VW Passat wagon� it was after the battery had died in my spare key (I had misplaced my regular keys). I replaced the battery but the remote still wouldn�t unlock the car. Fortunately, I also found the �hidden secret key� in the key fob which let me unlock and use the car (once the fob was in the ignition everything worked). The remote still wouldn�t lock/unlock the doors though� In the meantime, I found my �lost� keys (I had left them in a different coat that I hung behind a door and promptly forgot about). Once I used my �regular� keys, everything worked/works fine with the spare set again�

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What do you mean you "let key come back"???

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I’ll go test so I can better explain it or correct what I wrote.

I tried a number of variations like that and none worked. Good that you had some joy with your key.

So, I tested this morning. The key in the 997.1 TT has 4 positions, let’s call them P-1, P0, P1 and P2. When you insert the key it is at P0. After you move it to P1 (powers on car accessories) or past P1 to P2 to start engine key goes back to P0. After you have moved it to P1 or P2 and is has returned to P0 you cannot remove the key until you move it to P-1 which turns off accessories and/or engine, then it returns back to P0. At that point you can take the key out. Thus, unless you are physically turning the key, the key returns/springs back to P0. So, when I fixed my remote the other day, I put the key in (either with the button pressed as it went in or after it was in) and, with the lock/unlock button pressed, turned the key to P2 (without the brake pressed so engine did not start) and held it there for 10 to 20 seconds. Again, I do not recall whether any light on the dash illuminated. I then turned the key to P0 then P-1 (I cannot recall if i let go of the button or not when I turned it to P-1) and removed the key after it returned to P0. I did not have the button pressed by then but when I pressed button on key the doors locked. I pressed button again to unlock and got out, closed the door and locking/unlocking with the remote was again back functioning as it should be. I hope that adds more clarity.

Yes, that "re-sync's" the key..... Later 996's and 997's have a "Megamos Encrypto Secret Rolling Code" in the Transponder and Immobilizer that changes every time the key is turned on.... If the key has been in your pocket and the buttons get pressed a lot accidentally while not near the car, the key can get out of sync.... What you did re-sync'd the key to the Security System.....there is an official procedure but is pretty much what you did and I can't remember it verbatim...

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Good info! Thank you.