I just bought a 2003 AC 500 TRV. The coolant is not circulating. Temp light is coming on after idling for a few minutes. I tested the thermostat, it was not opening so it’s been replaced. The rad fan was seized, it’s been replaced. The rad is not blocked, it was removed and cleaned. Temp sensor in rad was tested, it’s ok. I just pulled the water pump cover, impeller looks ok. No in/out play. The top rad hose gets hot but the bottom stays cold.