New owner of 2010 PTT. (49K Miles) Check engine light (CEL), (yellow warning) x2 days
Scan showed multiple, mostly low voltage, faults(25 total in 10 areas). Battery was original with March 2010 build. Battery was recently recharged as maintenance after purchase using CTech 7002
Among the faults was:
P0597 Thermostat driver Which is diagnostic for either a bad sensor connection or faulty thermostat

After replacement of battery with Duralast Platinum AGM (AutoZone H8-AGM), the CEL returned and scan returned 2 fault codes. P0597again and

U0422 Ambient Temperature via CAN 1) Gateway control module incorrect or 2) Message via CAN defective or missing

All engine\seems to blast hot air on auto. (50F outside) so not much heater action.
Proposed courses of action Replace thermostat (948 106 034 01)
Questions:
Should I replace the water pump (948 016 033 01) as its off anyway to get to the thermostat?
I have seen mention of cracked/problematic thermostat housings if housing is original plastic? (948 106 080 01 ?) I'm assuming I should replace with (948 106 080 02) (aluminum?) is this proper or overkill?
Any other hard parts should replace while I'm in the area? Plastic radiator drain plug? (is this a thing? part#?)

Parts list:
948 106 034 01 Thermostat and Gasket set (PK970V6THERMO)
948 106 707 00 Thermostat o-rings included in above
948 106 533 00 Water pump gasket included with above and below
948 106 033 01 Water pump with gasket
948 106 080 02 Thermostat Housing
948 106 124 02 Gasket for thermostat housing
970 106 215 00 Drain plugs x2



Thanks for any help