This object reports the state of a second temperature sensor (sensor 1) on the Primary MPM, returning notPresent if the module type is mpm(5), and on other MPM types uses underThreshold to mean the temperature is not too low and overThreshold to mean it is too low, meaning this specific sensor pair checks for low-temperature conditions, unlike a typical overheating sensor. An admin seeing overThreshold here should not assume overheating as they might with a typical temp sensor; per the description this field flags a temperature that's too low, which could indicate a cooling malfunction like a stuck-on fan or a cold environment. A Primary MPM of the actual mpm(5) type will always report this as notPresent(2), so an admin querying it on that specific hardware type should not expect a real reading regardless of ambient conditions.