Motor and pressure keep cycling on and off repeatedly

it can be very difficult to have a washer not work properly. It sounds like the speed control is malfunctioning. The timer motor will not run continuously. It is the speed control unit that controls the timer and tells it when to advance. If the washer is repeating the cycles, then the speed control will need to be replaced.

most commom fault is a blocked or faulty drain pump

This is likely a cycling clutch. It cannot just keep going or everything would just freeze up. Modern systems run until they build enough pressure, then cycle off until that pressure depletes, then starts up again. This nets much lower energy cost.

Car systems do the same.

clogged water source

Check the refrigerant pressures. it may be turning off from low or high pressure limits with automatic resets. If you have a digital thermostat, there is a programming function in the installation instructions for setting the AC cycles per hour. If the AC is oversized, it will short cycle.

I have had a Hitachi EC89 compressor for a couple years now. As an Mechanical Engineer with a minor in Electrical, I observe that the motor assembly/capacitor is undersized for the mechanical energy it is asked to produce upon start up. The motor consistently struggles to get up to speed, requiring too much electrical current and then the breaker pops, and you're back to time zero. And the cycle repeats. In other words, the fundamental EC89 design stinks and it should not have been released onto the market in this way. I replaced the capacitor on mine with a more robust G.E. version and it has improved, but fundamentally, there are not enough motor windings to get the system going good & strong, each and every time. Shame on you, Hitachi.

The motor is holding pressure in the line.
Check the manual.
I don't think it is supposed to cycle that much.
If it's not designed to do that, then there is a seal or a bearing that is leaking.
It's letting water pressure escape the hose by letting water seep back into the pump.
The motor is pushing more pressure into the line to keep up with the internal leak.
Two times a second seems like a lot, and the noise is probably annoying.
If the unit is new, take it back.
If it's doing the job, run the equipment until it dies, or else take it for repairs.

We had a similar problem with a paint sprayer.
Paint sprayers also hold pressure on a line, except the fluid is paint instead of water.
When the machine sensed a loss of pressure, it would cycle once to restore pressure.
After a while it was cycling constantly, just like your machine.
Working indoors with the constant noise was a nuisance.
I had the machine rebuilt, and used it for another year before buying a heavier machine.
I don't know if there is a business that rebuilds your equipment, or how hard parts are to find.

If the fan and compressor are shutting off. its possible its cycling on a low pressure switch. probably low on freon.

or you have a low ambient kit to keep pressures up during low outdoor temps while ac is running just the fan will shut off, however thats not a typical thing to have a residential system

I am pretty sure it si not the pressure switch. pressure switch controls the amount of water per load. It appears your control panel has failed. You have many parts in this panel, however you can buy a complete panel and change it out.

you should check your pressure switch hose for a pin hole or better still just replace the hose and it should sort your problem out good luck hamstel