It should be underneath the driver's side door, unless it either doesn't have one, or else the block heater is an aftermarket installation.
If it's OEM installed, it should be directly under the door on the driver's side.
If it has one, it'll attach to the engine at the bottom of the oil pan, and, on some engines, the right side of the block.
Attached to the brake pedal.
There are 10 concrete block per m2.
Need to know WHICH Mercedes engine, as there've been a couple. On an M2, you probably have either the 6.4 or the 7.2 engine.
Need to know the transmission model in order to answer this.
Disconnect the battery, keep it disconnected for five to 20 minutes, reconnect the battery.
Code 128 whats is that for. Would it be egr
50
Bad fuse, bad relay, bad switch, bad wiring... take your pick.
The M2 family ranges from Class 5 to Class 8 trucks... weights vary greatly throughout, not to mention there's the matter of configuration (e.g., box van, dump truck, etc).
Question's a bit too vague to be answered with any certainty. Most likely, you either have a short somewhere, or a bad relay.