W203 Doesn't start/does not crank
I have a problem with my mercedes.
The car is a W203 2004 automatic 220cdi.
For the past month more than in 1 occasion I cant start the car.
When i insert the key i hear the ELV, then i open the ignition to position II i hear a "bzzzz" from the engine bay , when i try to start the car nothing happens at all! I switch the key to position III and it's dead,, no response at all!
The battery is brand new (i replaced it thinking it was the battery). When i turn the key to position II i see that the panel gives me random errors like ESP not working and Coolant System not working... then 2 out of 3 times that i tried the car would start if connected to the battery of another running car... while another time it just started without me doing anything... and whenever i manage to start it all the error codes are gonne and the car is 100% fine...
This is making my car unreliable and i cant drive out of town as i fear i will get stuck somewhere if i turn off the car ((
HELP ((

Check the starter relay
Check the starter motor
You could have an EIS that is failing.
Thank you for your answer. I checked the fuse52 and the fuse is 25A. Should i change it with 20A??? All the fuses you mention are not corroded and seem fine.
If it is a starter motor fault, why would it give the error messages about ESP or Water Coolant in the panel? Does that happen when the motor starter is faulty?
Another issue that happens sometimes is that i have a hard time with locking and unlocking the car from a distance. Checked the key at a key specialist and the key itself is fine. When it happens i need to be like 1inch away from the driver's door to lock and unlock the car.
I was told that it might be the front fuse and relay box. Is it safe to have it removed and checked if everything looks fine on the inside of the fuse and relay box? Do you think that can be an issue that gives this sort of problems?
Sorry for the long message but this issue is really upsetting and i am really trying to figure out what is happening with my car...
Thank you for your help!

The locking/unlocking from a distance is dependent on the RF circuit via the rear screen antenna operating properly & the key battery & transmitter condition. Once you put the key in the EIS it is inductively energised & does not depend on it's battery for the handshake. Close up you are depending on IR transmission via the drivers door handle sensor. Have you by any chance had a tint fitted to your windows?
The problem could be the front SAM but it is unlikely. It sounds like a failing EIS which is expensive. It could also be a CANBus issue or short.
Please get hold of an OBDII scanner & read stored codes & post them. The OBD Port is under the steering column under a rectangular cover.
See the handshake process from key to EIS in the Wiki so you understand what is going on & the start enable process.
If you can't give us stored codes I'm afraid you need to have the car properly diagnosed with a Star DAS at a dealer. Without guidance of the stored codes it is guesswork & you have multiple trouble conditions.
Last edited by Glyn M Ruck; Jan 13, 2014 at 07:46 AM.
Thank you for the very long reply and for taking the time to help me out
I had it diagnosed with STAR and most of the times the computer says it can't connect with the EZS ... then without doing anything... it manages to connect after a few trials and the only errors and faults i get are the Radio (which doesnt work because it has gone in safe mode because of disconnecting the battery) and an air conditioner issue.
All the other errors that appear in the panel when the car doesn't start are not there anymore (in the panel and in the Star test).
So when it does connect to the EZS it actually shows no relevant faults connected to this issue...
Regarding the key i had it checked at a electronic key specialist and he said the key is fine... its either the sensor or the program (according to him) but this is not sth that bothers me that much... the big trouble is the starting/not starting issue...
Once again thank you for your time and looking forward to your thoughts after the info above...
I was told today that it can be the front fuse box... they want to remove it and check it for problems... is this a possible option ? Is it safe to remove it and check it for problems?
Thanks
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... please keep your suggestions coming in case something else comes to your mind... thanks a lot

Good luck!
While they are messing around with the front Signal Aquisition Module tell them to check the starter relay in cavity S
Last edited by Glyn M Ruck; Jan 13, 2014 at 09:23 PM.
I changed the solenoid on the motor starter and cleaned the motor starter itself but it still keeps happening... now i am left with the option of messing around with the front SAM but i am not sure whether i should have anything in mind before doing that?
I was told i need to check the solder joints as they usually crack...
Additional info that might help is that 100% of the cases i am able to start the car if i connect the battery to another car's battery while their car is running... so if i jump start it then it is all fine, starts and the problem doesnt repeat itslef for another week or so... what can it be since jump starting works always... ????
Last edited by W203AL; Feb 14, 2014 at 06:03 PM.
I changed the solenoid on the motor starter and cleaned the motor starter itself but it still keeps happening... now i am left with the option of messing around with the front SAM but i am not sure whether i should have anything in mind before doing that?
I was told i need to check the solder joints as they usually crack...
Additional info that might help is that 100% of the cases i am able to start the car if i connect the battery to another car's battery while their car is running... so if i jump start it then it is all fine, starts and the problem doesnt repeat itslef for another week or so... what can it be since jump starting works always... ????
Often on this forum there are electrical problems you describe because of a low performing or faulty battery. You have replaced yours recently but I would like to ask whether it is one that has the correct capacity? (ie at least 70 Amp hour). MB recommend the Absorbent Glass Mat battery type also.
As you car starts whilst being jumped by another running car it points to your car needing extra voltage .
Why is this so ? Possible causes :-
Poor battery performance.
Corroded or badly fitted battery terminals.
Alternator or voltage regulator not charging your battery.
A system electrical leak discharging you battery.
A starter or solenoid which is worn ( brushes) & pulls extra amps to turn over your car.
Before expensive part replacements I would have a competent auto electrician check your battery ( load test) & alternator output.
What about putting a battery charger on overnight & see what the result is in the morning ?
Good luck.
JC

... it seems like its progressing badly... until today it was happening once in like 2-3 weeks... but it happened today like 3 times... and now the SRS says SRS Visit workshop..... since i live in a country with no very good Benz Mechanincs this is a very frustrating issue... no one is able to provide a solution here......
... it seems like its progressing badly... until today it was happening once in like 2-3 weeks... but it happened today like 3 times... and now the SRS says SRS Visit workshop..... since i live in a country with no very good Benz Mechanincs this is a very frustrating issue... no one is able to provide a solution here...... 
What is your battery voltage without the engine running for 12 hours or so ?.
Use a trickle charger over night to see whether the problem exists in the morning .
Or disconnect the battery neg. terminal over night to see whether the error exists in the morning. This is fraught with danger .Careful reconnecting ( key removed)as there is always a risk of Sam failures with voltage spikes.
Where do you reside or is the CIA after you ?

Check all electrical connections & earth straps.
Check the distribution block on the firewall for signs of burning or corrosion.

When you say won't start do you still mean "won't crank over"?
If your battery is healthy then you have a bad connection somewhere, A lazy starter solenoid or relay.
Also check temperature sender connection & CPS connection. Both are enterrogated before start enable.
Please refer to this links...
One video shows the case when the glow plugs sign doesnt shut off and errors appear...the other the case when it doesnt appear at all... in both cases when i turn the key, the car doesnt crank at all...no noise no nothing...
http://www.youtube.com/watch?v=7WkkM...ature=youtu.be
http://www.youtube.com/watch?v=UenS_...ature=youtu.be
Thanks for the time you are spending on this case



