Ty_SL516

Over the weekend I added a set of daytime running lights to my 2005 SL55. I ran the power wire to an unused slot/fuse in the passenger side fuse box. In order to get access to the unused fuse block, I had to remove the first "K" relay on the on the passenger side SAM/Fuse box. I wasn't thinking and used a small metal angled pry tool to lift the relay out from underneath. The metal tip of the pry tool touched one of the prongs/blades on the relay while pulling it out and there was a quick spark. I didn't think much of it at the time and continued working.

Fast forward to a few hours later and I completed my daytime running lights project and they work fine. However, the car is messed up now and won't start. In key position 1, everything is normal. When I click to key position 2, the engine cooling full comes on immediately and at full blast/power. I get a few error messages in the gauge cluster saying "display faulty visit workshop" and "ESP, ABS, ABC". Turning the key to the on/start position does nothing. As soon as I take the key back to position 1 or remove it completely, the fan engine fan stops immediately.

I should add that power windows, headlights, lock/unlock button, fog lights, electric seat adjustment, keyless go button, heated/pulse seats, radio, navigation, keyfob lock/unlock, trunk release, steering wheel tilt/telescope, etc all still work fine and normal. I can still lock/unlock the car from the keybfob as well.

From what I've read, the engine cooling fan will come on at high speed whenever the ECU is inactive or not sending a signal. I have a Eurocharged tune on the car and tried to "re-flash" the ECU tune hoping that it may of just gotten corrupted or erased. However, I get an error saying "unable to contact the DME, please make sure that it's properly powered on". I then tried checking the codes with STAR/DAS, erased them, and then tried checking again. The results are below. I checked every fuse in the passenger and driver's side SAM and they are all ok. I'm not sure how to tell if a relay is bad though just by looking at it? Also, I tried disconnecting the rear consumer battery and unplugging the ECU for 10 hours with no change.

So that's my story. I'm hoping that my amateur mistake didn't fry all of my car's electronics. I would think that they are fuses/relays to prevent this type of thing from happening though?

Any thoughts/suggestions that I could try before I tow the car to the dealer?

Ty_SL516

Here are the "current" codes after clearing the first batch from the original post.

I should also add that I tried swapping relays in the passenger SAM with no change as well. It looks like relay "K" controls the ECU and that's the one that I accidentally shorted. I also can't move the shifter out of park since the EIS fault code is current.

My only guess is that the ECU software/programming is now corrupt. I was thinking about mailing the ECU back to the tuner for their inspection and to have them bench flash it again if that's the problem. Is the ESP handled by the ECU or TCU? Other than that, I'm out of ideas?

carguyshu

the esp is handled by a computer that is right next to the drivers sam and the ECU. it appears tons of your CAN network is not functioning properly. I don't think it has anything to do with the software in the ECU as that would not make the CAN signal all screwed up like the codes you are pulling (a bad ecu or bad ECU programming shouldn't cause all the other communication faults)

The ME-SFI can communication fault is saying that there is a communication problem with the ECU, which is why the fans are defaulting to full blast as it is the default protection mode.

you also have CAN communication with the gear selector (the car wants to make sure it is in park or neutral before it will let you start it), the speed sensors (likely the transmission ones), the esp, the distronic module (on the early cars this was next to the TCU, but I think it later cars it is built into the sensor).

The ! signal next to the ESP and ME-SFI is saying that STAR can't even communicate with either of these modules at all.

Nor Cal SL55

I had a similar problem a several months back. Ended up being a SAM module (or so I am told). An Indy Mercedes Benz shop had it for a couple of months. The Indy was searching trial and error after a while and finally had to transfer it to another MB shop to resolve.

I couldn't get the car to turn over because the screen said "car not in park", when it was. Similar codes were present as yours... ESP, ABS, MF-SFI, etc. You definitely have a communication issue.

Take it to MB and have them fix it - unless you know of a GOOD Indy shop. I lost faith in the one I was going to. Saving a few bucks can cost you with these cars on electrical issues.

carguyshu

the downside to this is that they are likely going to buy a brand new sam module which can be $$$$ depending on which one it is. I accidentally screwed one of mine up and got a used one on ebay for $50. Retail on a new one would have been $935.

latemodel21

No SAM in this case, I walked Ty_SL516 through some diagnosis and helped him isolated it to the circuit 30 supply that passes through a 60 amp fuse that was blown (mounted next to the trunk battery).

everything is working again

Chris

carguyshu

chris is such the man

Nor Cal SL55

That he is!!!

I just wish I'd had him help me with my issue. Probably was a fuse in my car...