S.A.M. Unit grounded out 2000 S500 Please Help
01-12-2018, 08:42 PM
#1
S.A.M. Unit grounded out 2000 S500 Please Help
Today I pulled out the Right SAM Unit and without thinking to disconnect battery first "rookie mistake" I accidentally touched the main power supply to the SAM unit causing a big spark, Now when I turn the key I get nothing... but the aux fan comes on fast and wont shut off unless I unplug the battery. Also I can turn the key once but after the fan comes on it will not turn again until I unplug the battery. I am thinking a new sam? I tested the Pre Fuse and seems to be powered up have not tested the smaller red lines yet.
01-12-2018, 09:44 PM
#2
MBWorld Fanatic!
" I tested the Pre Fuse and seems to be powered up have not tested the smaller red lines yet."
Please tell us in exact detail what you checked and what you found. Be very precise and complete.
Please tell us in exact detail what you checked and what you found. Be very precise and complete.
01-12-2018, 11:01 PM
#3
Ok after the Big Spark, I tested the Pre Fuse under the footwell of the pass side floor, Tested all the fuses left and right "front" boxes" tested trunk Pre fuse on right wall, all seemed to be good (but) from reading, i did not know on the front pre fuse to check every single wire! there are two smaller red wires needed to be checked. I noticed where the Hot wire touched the SAM on the aluminum was burnt, so I opened the SAM and looked at the board and nothing popped out at me as being burnt. There is a Unit right next to the Right hand SAM that I have no Idea of what it is, but tomorrow I will check for burns on that but doubt it.
01-13-2018, 10:50 AM
#4
MBWorld Fanatic!
"... the Pre Fuse under the footwell of the pass side floor..."
There is not "a" pre-fuse there, but three. (Those may be the other wires that you need to check - but there are fuses.) In addition, the wires and connections must be carefully checked.
This has happened before to other people. Go to the top of the page, find "SEARCH", go to "ADVANCED SEARCH" enter suitable search terms in the box, scroll down in the list to "W220" and search. It might help to see what other folks had to do...
Do the same search on Google and other MB forum sites.
There is not "a" pre-fuse there, but three. (Those may be the other wires that you need to check - but there are fuses.) In addition, the wires and connections must be carefully checked.
This has happened before to other people. Go to the top of the page, find "SEARCH", go to "ADVANCED SEARCH" enter suitable search terms in the box, scroll down in the list to "W220" and search. It might help to see what other folks had to do...
Do the same search on Google and other MB forum sites.
01-14-2018, 07:31 PM
#5
Hello
Today I pulled out the Right SAM Unit and without thinking to disconnect battery first "rookie mistake" I accidentally touched the main power supply to the SAM unit causing a big spark, Now when I turn the key I get nothing... but the aux fan comes on fast and wont shut off unless I unplug the battery. Also I can turn the key once but after the fan comes on it will not turn again until I unplug the battery. I am thinking a new sam? I tested the Pre Fuse and seems to be powered up have not tested the smaller red lines yet.
however I think you damaged your eCU as fan on high indicates bad eCU . So second step is to replace 4 parts - key shifter eCU and ignition switch . All must be taken from the same donor car or it will not work . Cost about $350 for matched set of 4 parts in Ebay
