[size=13px]Hello all,

I just obtained a c320 wagon and I'm completely new to Mercedes (come from BMW and Audi world) and am hoping to get some help from those who know more about these cars. This car has a no crank, no start issue. I've searched the forums and googled around, but the answers there haven't helped much unfortunately. I bought an ancel diagnostics tool to get into the modules a little more and start diagnosing. My guess here is that drive authorization is failing and I am not sure why yet. Here is what currently happens:[/size]

1. Key goes in
2. ESL unlocks (and locks when key is removed)
3. Dashboard comes on
4. Key can rotate to all positions
5. Going to start position does nothing
6. Putting foot on brake and trying to shift the shifter works. Dashboard shows the correct shifter position.

Things I have tested:

• All the relevant fuses - 31, 52, 57 - and they are not blown. There is 12V to 31 and 57. I have also tested all the fuses in the engine compartment SAM and they are all good. All fuses have 12V except for 52.
• Fuse 52 does not get power when turning the key. I read that it only gets powered when the key goes to the start position, but nothing there.
• I removed the starter relay and shorted pins 3 and 5 and the starter kicked on. I also tried to run the starter while turning the key to start, but the car did not start. Just cranked.

Other notes:

• Battery was low, but I charged it up and all of this was done on a charger. Voltage was above 12V the whole time.
• The key does lock and unlock the doors
• The dashboard shows no actual data it seems. Everything shows "----". The car's total mileage does not show up. It popped up once for a short moment, but that was it.
• I removed the kickpanel to expose the TCM and unplugged it to try to start (looks clean, no water damage evident). Nothing changed, a whole bunch of errors were thrown.
• I have read that a bad ECU will kick the fans up to 100%. This does not happen. I can communicate with the ECU. I also took it apart, no water damage. Looks clean. Just to make sure everything was good, I re-soldered all of the pass through components on the board including the connector. No change there.
• I am able to communicate with all of the modules.

From the ancel diagnostics:
The ECU says

• Immobilizer: Active
• Start Enable: Yes
• Status of Drive Authorization: Transport Protection (What does this mean?)

The EIS says

• Control module EIS is initialized: Yes
• Control Module EIS is personalized: Yes
• Control Module EIS is activated: Yes
• When turning the key, the circuits are coming on and in start position, it detects that it is in start position.

The ESL says

• Control module ESL is initialized: Yes
• Control Module ESL is personalized: No
• Control Module ESL is activated: No
• The Transport Protection of Control: Yes
• Another note on ESL - when I turn the key to off, the two no's above turn to Yes. Turning it back to on sends them back to No. This is either due to loss of communication with the module or something else odd going on. Also when I am in the module with the scanner, sometimes the whole system locks out - key won't turn anymore. Then I have to back out with the scanner and it comes back to life. This is probably normal.

I found a few error codes -
ECM:

• Crank position sensor error and cam position hall sensor error. This came up after I cranked it by shorting the starter relay. Even if the crank sensor is actually bad, it should still crank over on start no? Just not start.

Dashboard - this one had a few weird ones before I cleared it, but it could have very well been that I unplugged the ECU and TCM with the battery still connected:

• B1123 Invalid Drive Authorization Data (Hmm..)
• B110D Fault in CAN Communication with Control Unit N22 AAC Pushbutton Control Module (Not sure what this was)
• B1103 Fault in CAN Communication with Component N15/3 ETC Control Module or ASG Automatic Gearshift System (I probably triggered this when I unplugged the TCM)

So anyway I am somewhat at a loss. I don't have a better diagnostics tool unfortunately (nor know how to obtain one). There was, however a lot more data associated with the modules, but I am not sure what they mean. Initially I suspected the ECU since it looks like someone had already tampered with it (and beat it up good, but inside it looked fine) and then when I read that Start Enable was good, I figured the ECU isn't the culprit. What stands out to me in the values is the ESL being not personalized or activated. But I find this weird, since it locks and unlocks just fine. Nor do I really know what "personalized" even means. I did read that that is supposed to maybe happen automatically? I bought an ESL emulator (which I should get next week) to see if the ESL is the culprit, but I am not sure. Not sure what to do next other than pull the ESL and see if it can be taken apart to be inspected. I think the EIS is fine given that all things there show yes. Any ideas on what to try next? Any help appreciated.

 

Well here's a reply to myself and updates.

I've been doing some more digging and I think the dash has been replaced. The mileage when it pops up on the dash shows 190k miles, but when I read the key with the scanner, it shows 220k miles. And I think since they mismatch, the dash just shows "----". This shouldn't affect starting though. I did some further testing with other stuff as well. I pulled out the SAM module and pulled it apart to see if there was anything visibly wrong with it. Couldn't find anything. To be certain anyway, I resoldered all the pass through components/connectors on the board to rule that out. Put that back in and no change. I did attempt a few key turns afterwards and to my surprise, it attempted to crank and fired even for half a second (or at least tried) then stalled. It did this a total of three times before going back to not cranking at all. I had a suspicion that it might be the esl module that was causing this as it looked brand then on the column. Today I got my esl emulator in and plugged it in. The emulator has a little speaker on it to make the "katchunk" sound as if it had locked or unlocked and it is doing that. However, still no start. Key turns and everything. So the emulator must be working... So I'm back to square one. I think this rules out the esl. So at this point maybe it's a bad key, bad ecu, or bad eis. I have no idea. Tomorrow I'll have the car scanned with Xentry and hope to find out more. I'll update when I do have the scan done. Thanks!

 

Ok

 

Final update here

So after a lot of failed scanning (and that friend didn't have STAR) we concluded that there was something wrong with the ECU. Gave in and took the car to a specialty shop who pulled the eeprom from the ecu and found that it was pretty badly corrupted. He wasn't even able to flash a good image to it. Instead, he swapped in another virginized ecu and coded the car. Fired right up. So all along it was a messed up ECU. Also turns out that the key and EIS have a totally different Vin than the car itself. So someone has already tried swapping those out.

I've had the car back for a little while now and everything is working properly. The cluster ended up showing the mileage from the eis, which is not actual mileage. Unfortunate, but it is what it is. After the ecu was replaced and virginized, the cluster also failed to program, so it got swapped out for another good virginized one. Hope this thread helps someone in the future. The immobilizer is one complicated system.