5volt chip Simos PCR 2.1

[verado]

Hello all in this fantasic forum.

My main buisness is repair marine ecu´s, and i have good experiece to those.

I have now Simos PCR 2.1 Vag car ecu that have wrong 5 volt signal.
I measure at bench about 3.3 volt on all 5 volt pins at A connector, but also measure 5 volt on some pins at B connector.
That makes me belive it is two 5 volt circuts at this ecu, and one of them is off by 1.7 volt.
I have DTC on pressure sensor after DPF.

What confuse me is that that rest of 5 volt sensors on engine does not show dtc even they recive only 3.3 volt.

So...i have attached pictures of several locations of pcb board to show parts.
>I have done the job by searching the web to find datasheets of those components at pcb, but i see some are secret.
So i ask here in forum...do anyone know what chip that regulate this 5 volt signal that i measure to 3.3 volt?

Best regards Stole Norway.

[servicemode]

i think it 's IC+fet
AITC91C4=power control
fet FZ24NS=power 5 out put

[verado]

Hello Servicemode.
Thanks, i look into this.

[verado]

And here is update.
On this vag 1.6 tdi engine haynes ecu manual is wrong ... it say that temp sensor before dpf should have 4-4.5 volt.
This is why i struggled, and asked of help here because my measure was only 3.3 volt.
So after some testing at ecu after help here...it came out that ecu is ok.
So what is wrong then....i got another work shop manual from Wurt.
And here manual say 3.3 volt from ecu🙄
Ok...back to basic. Ecu is ok.
Sensor is bad.
Changed sensor and all ok.
I know....do not ☺☺
Regards