sigmapiguy59

I am new here and hoping someone can provide some quick insight as I see this problem running a very large bill very quickly with no possible results. I have a 2009 E-350. My wife went to open the car this morning and the key fob wouldn't work. She then used the key to unlock the car. The car started up fine but the Red Battery Warning Light was on. She brought it to me at work and several features were not working:

1)Fuel Gauge Showed Empty
2) Key Fob Inop
3) Electrical Trunk release inop
4) Turn Signals Inop

Read 2 error message:

1) Red Battery Sign
2) Passenger Airbag off


I should also note that my automatic seat controls and power windows worked fine with no "syncing" required.


I drove the car without incident to the local mechanic. He hooked it up to the computer system and said there were a few faults related to the inop items above. He said he would need to change the Aux battery and all should be fixed.

He changed the Aux battery and the issues did not go away. Now he is talking about Rear SAM and BCM module.

My concern is I am stationed in South Korea and the parts are very expensive. I can order the parts myself but there is no guarantee that either of those parts will fix the problem. Too many times we become the victims of mechanics troubleshooting and us eating the costs. I have read several other posts with similar issues but nobody every seemed to answer and they kind of got off track. I tried searching all through the forums but found no resolution to this issue. My biggest questions are:

Why would a SAM go bad prior to replacing the battery? Everything I read said people had feature problems after the battery was replaced or as a result of jump starting which we didn't do as the car started right up. I hope you have some suggestions. Anything would help at this point as there is no MB dealer anywhere near me and the cheapest part number quote I received so far for a SAM was $600.

sigmapiguy59

Forgot to add, no matter how I turned the headlight switch, off, auto, on, headlights stayed on.

sigmapiguy59

Ok update... My battery was tested and it was a bit low. I got a new one and the system shows 13.4 if I test after turning off through the diagnostics. I left the auto shop and drove a while. The car starts fine and runs fine. I still have the following issues
1. Key fobs won't work
2. Trunk only opens with key
3. Battery warning light on
4. BAS/ ESP/SPS ? Diagnostics error/ says trig diagnosis ( sorry I am going from memory right now)
5. Fuel gauge shows empty
6. Turn Signals inop
Everything else seems to be working fine (AC/ Radio/ headlights/ high beams/ sunroof/ window etc.).
Mechanic says rear SAM is the issue through diagnostics but it seems to me based on the SAM/ fuse chart that all items are controlled by different modules. I am desperate here because I have to order parts from the states and I don't want to do any damage but need the car to get to and from work. Any help is appreciated.