Thanks everyone for a quick input.
My thoughts at the moment.
Why would anyone go through the hassle of erasing such a code? An OBD service expert told me over the phone that you have to be a serious coder in order to be able to know how to do such a thing. They thought I should send in the cluster so that they could check all the wiring and soldering, to see if someone managed to solder wires together in a way to block off the signal. Maybe worth trying. They estimated 200$. That was gonna be their first place to check.
What calmed my nerves were youtube videos. Must have found a dozen of clips showing the cluster at start of the ignition and every diesel (you can tell by the cluster) didn’t have the check engine SES light up. The gas once did!
I took that with me to the smog place and said that this is how it is “It’s designed not to come on��” which is probably b.s., also showed the inspection person the cluster test. Which acts perfect. So I passed. Now I’m just wondering if this is just gonna worsen for every year. Continuously failing and failing every smog because this SES no show light.
How is the SES acting in your car. Specially if you have an e53 3.0d. Does it turn on at the start of the ignition? Just curious.
Thanks again everyone.