CLK55 W209 Flat battery on car and can't get in witth key!!!

[L555_BAT]

I just went to my car (05 CLK55 with keyless entry) and the door would not unlock. They keyfob seems to be ok as the LED is still working. The strange thing is that I can see a blue headlight symbol alight on the dash of the car. I presume this should not be there? Maybe it has flattened the battery? I only used it at 2pm yesterday and would have noticed if there were lights left on as I can see my car in the car park and night and it's pitch black.

So I have taken out the emergency key and turned it 90' anti clockwise and that will not unlock the door either!!! I have sprayed the lock with WD40 but it didn't seem seized in the first place.

So im well knackered.

Please can someone tell me how to get in the car without breaking in and what the headlight light is doing lit up on the dash. I don't even know how to put parking lights on so maybe I did it by mistake? If so the car was not light up when it got dark later that day

Thanks in advance!

[L555_BAT]

I forgot to mention that I can unlock the boot. I don't suppose there is a way to get in via the back seats. It's also a cabriolet.

Please help..

[SLacKer]

Not sure of keyless go but do you have a small rectangular window next to the lock. If so you can use the infra red of the key by getting it real close to the handle and unlocking.

If you can get into the boot then do you have a 12v socket? You can get trickle chargers with these as a fitment so you could charge the battery from the boot (this only works if the socket is not ignition controlled). You could also pull the boot light out and use that +ve to charge the battery.

Battery drain on these cars can come from the seat controllers which develop a fault where they do not switch off and drain the battery quickly. Of course it may not be this but it is something to consider.

[L555_BAT]

Thanks for taking the time to reply. I called the garage out. They powered it up via the alternator then I unlocked it and jump started it. The battery is fine and so far the mystery light has not come back and the battery is staying charged.

As for the door lock someone put the infared sensor in wrong or something and was jamming up the lock. The garage has taken the door panel off and fixed it. (All ok now touch wood)

Regards

Clive