Cooling fan control switch

1988 Regency Brougham .....where would I locate the cooling fan control switch?

There is none, the coolant temp sensor reports engine temp to the pcm , a relay is commanded by the pcm when the temp reaches 222 or the ac is engaged.

Would that mean then that there is a problem in the pcm? The dash gauge shows the engine is getting hot but it seems the fan does not engage. The car is fine as long as I am moving but I cannot idle for more than just a few minutes.