They are 6 way connector blocks and supposed to have a test port but its so tiny I am not convinced my meter probes are correctly in so I used a spare wire hole instead and have 0Vs. I have left the probes in and the heating controls to on and will monitor the meter whn the temp drops and the system fires up like it has been doing.I’m not joking. Create a demand (heating on) one probe in blue, one probe in orange, if you get 0 volts, then keep the probe in blue and test other orange, if you get less than 240vac on the heating then you have found your issue.
One thing I noticed is that the orange wire from the motor in question was not fully inserted in the push fit connector but had been this way for 11 years. I have now pushed it fully home.