Charged battery while still connected to terminals now SMARTKEY / FOB wont operate

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Nov 24, 2013 | 12:45 AM
  #1  
Hello, I Went away for a few weeks and when got back put the charger onto the battery terminals while they were still attached to the power cords going to the car, in other words I didnt disconnect the battery, just charged it while still connected, anyway probably should have known better, so now the smartkey / remote fob wont operate either the ignition or the unlocking of the doors, I have used the retractable key blade to get into the car but cant start it ! Has anyone got any ideas on what to do ?? does it need to be reset with a star diagnostics ?? Im sure if I ring mercedes they will push me down the " just buy a new key @ $475 in Australia and all will be fine ( no way )

its a 2006 c180 coupe

any options or ideas welcome

cheers ash
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Nov 24, 2013 | 12:53 AM
  #2  
Whoops forgot to mention its a 2006 c180 coupe that we are talking about
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Nov 24, 2013 | 01:52 AM
  #3  
You do not mention if you have a spare key and how the second key behaved.

Quite often the power coil fails at the key but this only prevents the key working at the ignition slot, doors should still work. W203 cars have also had EIS issues at cold temperatures but again, door locks should still work.

What sort of a charger did you use? If it was a typical low amp charger, it is certainly better to use it with the battery connected as you did. Otherwise you might blow up the rear SAM (if not others).

Did you check the battery voltage? Did you check all fuses? What happens if you turn lights on? What happens when you insert the key to the ignition slot, nothing, does not even turn?
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Nov 24, 2013 | 02:27 PM
  #4  
Quote: You do not mention if you have a spare key and how the second key behaved.

Quite often the power coil fails at the key but this only prevents the key working at the ignition slot, doors should still work. W203 cars have also had EIS issues at cold temperatures but again, door locks should still work.

What sort of a charger did you use? If it was a typical low amp charger, it is certainly better to use it with the battery connected as you did. Otherwise you might blow up the rear SAM (if not others).

Did you check the battery voltage? Did you check all fuses? What happens if you turn lights on? What happens when you insert the key to the ignition slot, nothing, does not even turn?

Thanks for your advice, I dont have a spare key, the first two gos with the key you are correct it unlocked the doors but wouldnt turn the ignition, then on the third go it would work with anything, I have replaced the batterys in the fob, still nothing, I have unconnected the terminal on the battery also, but nothing changed, the stereo and lights will turn on still and the battery voltage is good, it was charged with a ctek which are short circuit proof etc etc

temps here are warm close to 85 - 90 degrees

which leaves fuses, which ones should I check ?? I have found the box near the windscreen but no map etc or anything ??

cheers ash
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