C-Class W204 2010 key fobs have went down ?

[xtremem23]

Guys bit of a problem and was hoping for some advice.

Yesterday;
Drove to work, went to lock car with key fob and doors would not lock, right up to the IR sensor in handle made no difference.
Inserted key into ignition switch and turned key, no lights come on dash, well apart from mileage bu this comes up when opening the door to enter again.
Turned key few times but still nothing, then "key initialising" popped up on the display, left key in ignition for 1/2 n hour or but still said the same.
Removed key.
"steel key" only would lock the the drivers door, all other remained in the unlocked state, is this normal operations ?
Went and got spare key and the spare key locked and unlocked,started car as normal so i had to use the spare key to get the car home ignition.
Parked up and left overnight.

Today:
This morning, already knowing the first key was not working even after replacing batteries i again went to use the spare key and nothing, exactly the same as the first but now the car will not unlock the doors, didnt have time to check if it works in the ignition as i was heading to work.

Anyone any ideas ?
It's as if they are losing their code or something ?

Cheers

 

[JBell]

Sounds like an EIS (Electronic Ignition Switch) problem

 

[umblecumbuz]

As above. EIS possible cause.

 

[xtremem23]

Looks like im unlucky.

Replaced batteries in spare key and it now opens doors and starts car.

The key i always uses looks like it has just lay down.Had it on Star there about 15 mins ago and no faults are reported with EIS etc. and using spare works fine after second battery replacement.

Anyone here of a key just lying down like this, red led lights up and infrared checked using camera but it aint doing what its meant too

How much is a key, i m sure its silly money no doubt and only from dealer

 

[Naraic]

There are two problems surely? The lock function and the ignition function being separate . But then that seems to be a huge coincidence.

Edit. The batteries are not required in the key to start the car...just to open the doors.

Key is about £220.

 

[xtremem23]

Naric,

Totally agree with you, central locking works on infrared/RF and ignition on induction coil from car but both works using the spare key after replacing its batteries.

Thats why i was asking if anyone has had this issue, im sure im not the first and i understand that components do lie down, just seems strange.

When on xentry, both keys were tried but first key didnt throw up any fault in EIS or Xentry and spare just worked as normal.
Its like the key has totally lost its sync with the car, is that possible ?
Like i said it did once come up "key initialising please wait" but didnt do anything more.