About P1645-1351-0234 fault codes.

I'm having a problem with not exceeding 3000 rpm while driving on the road in my vehicle, especially on the long road. When I read the forum topics, the source of the problem is the solenoid valve failure in most people, I took it to a master who does turbo repair because it's probably the same for me, he checked the connections, looked for leaks, finally connected it to the computer and told me the fault codes that I will write below. I was told to change the glow plugs and then come back to him. I showed the fault codes to the master you took for the glow plugs, and he said that the change was risky and that the glow plugs would be needed in winter and made me give up on the change.

The error codes and their descriptions are ;

P1645 : accelerator pedal hard point signal failure for vehicle speed limitation consistency

P1351 : pre/post heating relay circuit relay contorlled andd spark plugs not supplied

P0234 : Turbo pressure regulation measured turbo pressure is too high

About 3 months ago, I had the engine repaired due to oil leaks and had most of its parts replaced, including the timing belt (approximately cost 4 thousand TL). Also, I had an amplifier fitted to the vehicle for compelling reasons. During this process, I also had an aux connection made. Extra cables etc. were installed for these, I don't know if they can trigger the above fault codes or if it is caused by glow plugs as the master said. Frankly, I have never had any problems with the operation of the vehicle in winters. If any of you friends have these problems or have knowledge about the subject, I would appreciate it if the answer informs me.