Fob won't stay synched

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Jun 15, 2018 | 03:10 PM
  #1  
I have a key fob that won't stay synchronized.

When I follow the normal procedure (key to position 2, remove key, hold lock while pressing unlock 5 times, then press either unlock or lock), the car responds to the final key press (lock or unlock). But after that, it ignores any key presses from the fob, with the exception that it will respond if I try the lock+5x unlock+whatever again without putting the key back in as long as I'm still sitting in the car.*

For an additional test, I took the batteries out of the ML320 fob and tried to see if I could sync the key for my SLK320 to the ML320, but that didn't work at all. Possibly because the SLK320 was within range of the key? But it suggests to me that buying a used key and transplanting the physical key might not work.

*Correction: It will also respond if I do the resync procedure immediately after exiting the car, which lets me lock the car using the fob, but is terribly awkward.
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Jun 16, 2018 | 05:45 AM
  #2  
You are on the wrong forum.

https://mbworld.org/forums/slk-class-r170-8/
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Jun 16, 2018 | 12:44 PM
  #3  
Maj. Dundee, you are incorrect, but I can see where you got confused. I've got both a ML320 and SLK320. I'm only having key fob trouble with the ML320.
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Jun 26, 2018 | 01:58 PM
  #4  
Update: If I exit the ML320 and close the doors, then lock the doors as the last step in the resync procedure, then unlock the door using the key, the alarm goes off until the key is inserted and turned.
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Jun 27, 2018 | 06:05 AM
  #5  

Quote: Update: If I exit the ML320 and close the doors, then lock the doors as the last step in the resync procedure, then unlock the door using the key, the alarm goes off until the key is inserted and turned.
After you have locked the car with the key fob and later use the key to unlock, the alarm will sound. This is normal and working as it should. Read your owner's manual.
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Nov 21, 2018 | 06:27 AM
  #6  
Hi Jaron, any luck on this issue (ML320 key fob not working) - I have the same issue exactly like how you described it.
I have tried a lot of things but no luck yet.

I also paid a local "mb mechanic" with no luck and only conclusion is AAM faulty - I am not 100% this is true as only 1 key went bad at first, the other one went bad after a few months. now both keys bad.

any update would be appreciated.

thanks.
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Nov 21, 2018 | 09:59 AM
  #7  
I was not able to fix the issue and have since sold the vehicle.
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