Hi guys. I have just joined today after purchasing my 2004 e320 cdi advantguard 2 weeks ago. 4 days after i bought it, i started having a few electronic problems. I have had the car to a few mechanics around but there is no MB specialists in my area. I will try my best below to explain the cars symptoms and any help would be appreciated. Sometimes when i go to start the car, the ignition lights come on and everything works.... but no start - nothing. If i mess about for a while with it, it will eventually start but then nothing works... no wipers, windows, nothing on the dash etc etc and strangely the engine fan comes on full time and the car will drive perfectly. Then sometimes when i switch the ignition on there is completely nothing... no dash lights etc. The last thing i have noticed is as with any mercedes when you place the key in the ignition or remove it, it mades the funny noise as usual, BUT on my car when i place the key in the ignition i have to hold the UNLOCK botton for the unit to make the noise and then it lets me turn the key. It wont make the noise when i put the key into the ignition until i hold the unlock button and then its lets me turn it. I know this is not correct. Would this be the SAM units, or the EIS key unit?Any help would be grateful.