OBD2 scanner is just translator

I built a full OBD2 system on my garage floor from an Alfa Romeo wiring harness. Engine ECU, cluster, ignition module, sensors… everything.

And in this video I show you the core truth about OBD2 scanners:

**🔑 A scanner is ONLY a translator.

It does NOT create features — it can only request what the car already knows.**

Your engine ECU diagnoses engine faults.
ABS module diagnoses ABS faults.
The instrument cluster diagnoses cluster faults.

The scanner doesn’t diagnose anything on its own.

It simply takes the car’s “language” (CAN messages) and translates it into something you can read.

And when you press a button — like “activate fan,” “reset service,” or “run a test” — the scanner is NOT magically performing anything.

**It just sends a request.

The car must already support that request.**

If the car doesn’t know that function,
if the module doesn’t support that command,
or if the system wasn’t designed for that feature…

👉 No scanner can force it to work.

That’s why some functions work on one car and not on another — even with the same scanner.