I finally got an E-Class a couple of months ago and for the most part I love it. I upgraded from a 2004 C240 so the difference is noticable. But it seems like a bunch of random little issues keep popping up and I want to make sure I'm dealing with them correctly. Treat the "disease" and not just the symptoms.

Let me start from the front of the car.

Horn - sounds like a dying goose. Sounds to me like either the woofer or tweeter horn is not working. Is it a fuse issue, the horn or electrical.

You'll see why I say electrical in a bit.

Headlights and instrument panel - Headlights and instrument panel lights dim momentarily once in a while like there is a drop in voltage. Is this normal? A battery issue? or alternator starting to die?

Transmission - I've already had to have the TCM reset because about 3 weeks after I bought the car, it started to shift weird. Wouldn't shift out of 1st or second. And then wouldn't come out of 4th or 5th. The next day, starts up and drives fine. Drove it straight to the selling dealer who "sent it out" to a Benz specialist who then reset the TCM.
I'm wondering if there is in fact an electrical issue, if that affected the TCM and cause the erratic shifting? It happened again a couple of days ago where it would downshift hard between 2nd and 3rd or 2nd and 1st. Then it drove fine the rest of the day.
My indy shop recommended I change the transmission and transfer case fluids/filter because it didn't "look like" it was ever done.

Rear driver's side window - Again randomly, seems like the window decides it doesn't want to work. Doesn't go down or up using either the rear passenger window button or the driver's window button. The door lock also goes out of sync. It does that for a bit. I'll go somewhere, come back to the car about an hour later and the window magically works again and the door locks are synced.

Rear defroster and radio - When I turn the rear defroster on my radio reception is very staticcy. I've read that this is an issue on some cars but could this be related to the other issues?

And lastly the trunk - In y research I found some posts that mention that there would be a water leak in the trunk that could affect the battery and electrical wiring. It rained yesterday, I looked in the trunk, under the carpet and near the battery and there was no water or moisture whatsoever. I do notice that when I open the trunk after it has rained, water seems to leak out between the exterior skin of the trunk and the interior metal seam on the left side. Could just be water running in from the exterior but not sure

Anyway….I know it's a long post and thank you for reading so far.

Could all these issues be related to each other? or am I having a bunch of unrelated problems happening at the same time? What can you recommend I do? or start to do?

I've haven't had any luck getting the VMI for my car from the dealership. I was hoping that would give me an idead of what's going on because clearly the previous owner didn't take good care of it.

Thank you.

 

I suggest you get to know your typical battery voltages (I forget if you have two batteries or one in your model). It is an inexpensive thing to check your battery voltage and get an idea if you may have an old battery that is on its way out the door and causing issues.

 

1 Battery in 07 >. (No SBC Backup battery)

 

That's correct, only 1 battery.

When I read the voltage from the MFD it shows: UB 12.3 V (actually it switches between 12.3 and 12.4) and then on my inspection report it says: Pin 16 Volts Check - 14.2

 

14.2 V is a good battery ... 12.3 V is a might-as-well-be-dead battery. Try a new battery to see if your glitches disappear. Good luck.

 

As for the horn,

Purchase an aftermarket air horn, its plug in and play

My W211 dims on the occasion, so i think it's normal for the w211's

 

what brand horn?

 

willy_manilly, I'm not sure that I want to class it up that much

 

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