1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Dismiss Notice

Water damaged key

random101 Nov 13, 2017

  1. random101

    random101 Registered User

    150
    0
    16
    Hi all,

    I dropped my key in the water at the boat ramp... since the remote has died (changed the battery and it worked but shortly there after died again even after pulling it apart and giving it a good clean).

    Never the less the key still works without the remote.

    So I bought a used key and was hoping to switch my blade into the used key and reprogram that key (possible)?

    I tried to do it with out a VCDS / Rosstech and it looks like I've tripped the Immobilizer.


    Thankfully I have another key that works fully.

    My question is - can I use the two key method (one in the ignition the other in the car door to reporgram the key) or do I need a VCDS.

    Alternatively - Do I need to transplant anything from the current transponder chip into the used one that I bought? If anyone has a depth of understanding on the matter it would be greatly appreciated.

    Edit - The car is a 2015 A3 8V, with a key start.

    Cheers.
     
  2. Avatar

    snack-media
    Advertisement


  3. random101

    random101 Registered User

    150
    0
    16
    Key with replaced blade starts the car, though the windows wont work with the key haha.

    Hopefully VCDS can activate the key?
     
  4. Ormesome

    Ormesome Registered User

    1,923
    1,136
    113
    Dunno about VCDS but around a year ago i had a key done by Audi, was told at the time by numerous locksmiths/car techs that directly through Audi was the only option as they ordered it directly from Germany, with all the codes to be specifically for my car. When the key arrived my car had to go in to be programmed. Was a round £200-£250. @DJAlix might be able to help though.
     
  5. DJAlix

    DJAlix VAG Car Coding™ Limited Site Sponsor Gold Supporter VCDS Map User VAG Can Professional ODIS (Offboard Diagnostic System)

    6,471
    4,958
    113
    Keys can only be programmed via the official VW Group application at the moment and even a good locksmith cannot do it. You will need Audi or an authorised 3rd party (such as myself :) )
     
    Ormesome likes this.
  6. random101

    random101 Registered User

    150
    0
    16
  7. DJAlix

    DJAlix VAG Car Coding™ Limited Site Sponsor Gold Supporter VCDS Map User VAG Can Professional ODIS (Offboard Diagnostic System)

    6,471
    4,958
    113
     
  8. random101

    random101 Registered User

    150
    0
    16
    Hm, so then though the transponder in the key blade is still good (is this correct?).

    The radio in the key to talk to the car still needs the official VW group to set it (I assume the pin)?

    So I don't have any alternatives bearing in mind I have the original key & blade.
     
  9. DJAlix

    DJAlix VAG Car Coding™ Limited Site Sponsor Gold Supporter VCDS Map User VAG Can Professional ODIS (Offboard Diagnostic System)

    6,471
    4,958
    113
    Am not gonna pretend to know why the key is only partially working as that’s not my area of expertise. What I do know is that VW group have not released the the information needed to allow 3rd party applications to be able to code or indeed adapt MQB or MLBevo keys. Only Audi or people with the official VW Group application can work with keys and IMMO on these cars.

    The Ross-Tech information you have found relates to cars pre 2009, and maybe before that.
     
  10. random101

    random101 Registered User

    150
    0
    16
    I noticed that when I read up the second link regarding the immb.

    So I tried again with the blade in the used key fob - it didn't like it and locked up (I think it started because the other working key was there when I tried the first time the second time I had just the original blade and the used key and it locked up).

    Started again with a working key all fine.

    Tried the blade back onto the key with the water damage and it starts and works fine.

    I can live without a remote.

    So the locksmiths offering replacement keys - are the able to encode new keys? I don't understand how they are getting past the official VW hurdle?
     
  11. DJAlix

    DJAlix VAG Car Coding™ Limited Site Sponsor Gold Supporter VCDS Map User VAG Can Professional ODIS (Offboard Diagnostic System)

    6,471
    4,958
    113
    Are they offering a "working" replacement key or a "replacement" key that will need coding?

    Anyone can order a replacement key that needs coding, or a blank that needs cutting and coding. If they are offering a "working" key then they either have the VW Application or know someone that has. Cutting the blade is something only a locksmith can do though.
     
  12. Avatar

    snack-media
    Advertisement


  13. random101

    random101 Registered User

    150
    0
    16
    So - I've posted on the Ross Tech forums.

    The above is correct with out SKC we cant program the keys - and you can only do new keys at that.

    So here is where it gets interesting.

    I took the water damaged keys immobilisor chip (the long black rectangle) and soldered it on the used key and went to start it thinking it would be okay.

    Nope- locked up straight away.

    Soldered it back onto the water damaged key and it worked fine. I'm not sure if I have the right chip but it's certainly confused the hell out of me.
     
  14. AJB

    AJB Registered User

    270
    79
    28
    Things may have changed on more modern cars, but my understanding in the past was that the immobiliser chip was passive, getting any power it needed from an inductive connection to the reader in the steering column. So, I wouldn't have expected it to be soldered to anything...

    Like I said, I might be completely out of date or just plain wrong though.
     
  15. random101

    random101 Registered User

    150
    0
    16
    Neither did I - I thought it was in the key blade.

    I'm not sure why it is soldered to anything as it has no power - I'm using it without a battery (on the water damaged key).

    No idea why the used key didn't like it (locked up the car).

    So I'm more confused then ever...
     
  16. AJB

    AJB Registered User

    270
    79
    28
    I wasn't expecting it to be in the key blade. On older designs it was a separate passive chip contained in (clipped into or stuck onto) the plastic housing of the key, along with the active battery powered radio circuit for the remote locking but completely (physically and electrically) separate from it.

    Perhaps they've now moved it onto the circuit board as a way to locate it? The thing you moved/resoldered - does it look like it's electrically part of the circuit board (tracks going to/from it), or does it just look like it's soldered on as a mechanical way to hold it in place?
     
  17. random101

    random101 Registered User

    150
    0
    16
    It looks like the circuit is connected to it. They also used a heap of epoxy to hold it in place.

    I'm just baffled as to why it didn't work on the other key. yet it works on the board/key with no battery.

    Maybe makes me think I didn't have the right chip. Key.jpg

    The red dot is the one I took out (note randome key but same design).
     
  18. AJB

    AJB Registered User

    270
    79
    28
    That's weird - from a quick google it looks like you've got the right chip, and that they've changed the design from the older ones where it was a completely separate small chip/device.

    I'm kind of not surprised it's still passive and works without a battery - I guess the logic being that if the battery goes flat you can't use remote locking, but you can still drive away having unlocked with the physical key.

    Is there any chance you soldered it on the wrong way around? If it's electrically connected for whatever reason (perhaps the passive RFID stuff is on the ciruit board and it's just an ID, or perhaps the antenna is on the circuit board, or something), then it might be polarity sensitive...
     
  19. random101

    random101 Registered User

    150
    0
    16
    I too was considering this or I damaged the other board. I don't really want to be pulling it on and off as I might damage the boards or chip.

    Unless I knew for certain it may work as I'm just experimenting at the moment.
     

Share This Page

Do Not Sell My Personal Information