Miconic A/M FHU Error

I have a Miconic A/M that has lost the FHU before and usually I would just connect the HHT and perform the fhu but this time around it’s not taking it, I can perform it and the car will run to the top and then the bottom but when it’s done it’ll still say FHU required and on stats>car>ftr it says 30:init FHU nvr bad. I check that it’s not missing any DZ flags and it is seeing the LU DZ LD on controller for each floor any suggestions I might be missing? I don’t have a lot of documentation on these.

the MTV board battery backed ram has lost the table of learned floor position counts. check the onboard 4.8v battery. measure the voltage at the mtv board p17 connector. p17 is located just beneath p14 on the lower right hand side of the mtv board. the voltage at this point should be no lower than 5.00vdc. adjust ps1 power supply to get this value.

Hope this helps