Repair of PMM Bosh SRV55TO3EU/37, poor quality of dishwashing. ⇐ Bosch

[Reed]

The hostess complained about the poor quality of dishwashing.
A test cycle was carried out on the "intensive washing 70 deg" mode. Before starting, the indicator showed something like 125 minutes.
The pre-wash stage seemed to go well: the machine was vigorously splashing from all the impellers, the water temperature was close to 50 degrees.
The main stage / the intermediate wash was strange: water flowed out of the impellers weakly (if at all), the water temperature was 25 degrees (it wasn’t close to 70). This continued until the indication reached 1. Three hours passed until this moment (that is, a very long time). During this time, when I approached, the machine kept making sounds similar to pumping out water, but maybe I’m confused because the impellers were wet, however, the detergent powder was not even partially washed out of the opened container - it remained in the container in a wet state all this time.
Then, during the next approach, I saw the number 78 on the scoreboard, which further decreased. At this time the machine began to water well again. I believe this was the rinsing stage, but the water temperature was about 25 degrees, and it wasn’t 70 either. At this stage, the powder was washed out of the container.
Eventually the display reached zero and the washing stopped. The total washing time was about 6 hours.
In the last 8 operating cycles of the machine, E1 is present from the service menu.
When running the P0 test, the temperature inside was very hot (I think it was 70 degrees ). The test had 14 steps, the test lasted about 20 minutes.
Regarding the test: maybe I did something wrong - I’m not sure: I don’t have a service manual, I selected it at random. I have scraps of information regarding indication and diagnostics.
Please tell me what could be the reason for this operation?
Also, if possible, please help with the service manual, electrical diagram...
Repair of PMM Bosh SRV55TO3EU/37, poor quality of dishwashing.