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Discussion Starter #1
I dropped my keys down a drain (dont ask how);oops: and my key fob got wet. it was working at first, but after about 4 hrs, it quit working. It is my only fob, is it still salvagable, or will i have to replace the twice unit?
 

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Try taking the battery door off, remove the battery and dry it thoroughly with a hairdryer on low heat. If you do get it working get a spare key sorted pronto, its a lot cheaper than replacing the whole system.
 

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how should i clean it, just pour it all over it?:roll: i am really getting upset because it rains here everday... really hard. i get soaked trying to unlock or lock the doors.
 

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I've gotta ask, how does pouring rubbing alcohol over the fob clean it? I know alcohol will evaporate, but surely the last thing you need to be doing is adding more liquid to the equation. :roll:
 

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once the alcohol evaporates it won't leave any electrolytic conducting material behind.

Pure clean water shouldn't be to bad for it, but get it dry ASAP

(Speaking from bitter personal experience, coffee and MRI machines do not mix...);oops:
 

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uncc 9-5 said:
I dropped my keys down a drain (dont ask how);oops: and my key fob got wet. it was working at first, but after about 4 hrs, it quit working. It is my only fob, is it still salvagable, or will i have to replace the twice unit?

That's not so bad. My mom put her keys on the stove once and then they fell into the grate and were forgotten about. THEN she placed a pot on the stove to boil and completely melted the fob. The electronics were burnt and hanging out of the shell....it was crazy.


For your water, I think it will be fine.

My nitro r/c monster truck got rained on once and then the radio reciver worked very erraticlly. I took it apart and placed it over a floor A/C vent in the house. 2 hours later, I came back to it and it worked fine.


My advice is to take the fob off the key, open the cover and place the circuit board over some source of moving air in a dry location for a day. Check it's operation after that.
 

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When the battery needs to be replaced, the keyfob adds an extra message which will be displayed on the SID. The fob will still work for some time. Consider it a friendly warning message.

When the battery shall be replaced, you will have to do this in some 20 seconds or less. The circuitry stores the [known]key ID in CMOS RAM backed up by the battery and possibly some available capacitance on the PCB.

If the battery change is done in less than 20 seconds, all is well.

If that time limit is exceeded, the key code in the FOB is lost. The key will then have to be re-linked to the car by using Tech-II and the key.
 

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I work at an electronics manufacturing company and here's how we deal with electronic components that have been exposed to moisture.

You can bake it (yes bake it) in your oven for an extended period of time.

I don't know what the melting point of the plastic in the keyfob is, but if you set your oven to a reasonably warm, but not hot temperature, remove the battery door and betteries, and leave it open, and leave the fob in overnight, and then replace the batteries, it might just work.

As far as the temperature goes, I'd be guessing for the keyfob, but my assumption is that you wouldn't do any harm to it if you leave it in there at just over 200F (boiling point of water) overnight. At that temperature you'll cook off any moisture, yet not have to worry about melting any solder that may be inside.

The only concern is th emelting point of the unknown plastic they used in it. My best guess would be that can handle just over 200F fine though... To be save, put it ontop of some cloth or something so that the plastic isnt directly touching any metal in the oven.

--Matt
 

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Uky,

I am not sure about that, I left the battery out of mine for quite a while (over 1 hour) and it had no affect.. :) the info must be hard coded onto the chip otherwise I agree with you I would have lost it... I wouldnt have liked to try it for any longer but my gut feeling is that its all hardcoded.. Which would prevent the data being lost should a flat battery be left or completely removed in/from a keyfob for an extended time...

Michael
 

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The information I have from SAAB is that a random master code is generated upon insertion of a battery and that a Tech-II is used interactively when a keyfob is to be put "activated" for use with a specific car.

If the battery was taken out of the fob, it had to be replaced within ~20 seconds or the master code would get lost.

The key is supposed to use the master code + a rolling code so that two code messages sent are never the same. This would prevent anyone from recording the code and retransmitting it later.

Thus, if the keyblade fits, any radio unit can be made operable with a specific car. My previous 9-5 had 4 keys (The two original ´98 BIG keys, and two with the newer design that came ´99 or ´00.) (I got tired of having my pockets ripped up by the keyblade flipping out all the time, so I ordered an extra pair of keys.)

When I went to check on a brand new TWICE unit I have in my garage, I saw that the unit comes with a 433.92MHz receiver and two key RF-units with mounted batteries and labels with serial numbers on them, so I am not that sure anymore...
 
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