If you are having this problem even when the engine is cold then most likely you have a faulty temp sensor (like gillybenz stated). However, if your problem is only once you reach working temperature then you probably have a faulty resistor (which would make fans work at high speed only).
BTW if the coolant sensor is faulty I wouldn't leave the wires bridged. Especially if it's very hot in your area and if you operate AC. Your car will definitely overheat. If it's pretty cool outside you could probably leave it and monitor temp like gillybenz explained.
Gilly: I've never seen a high press switch stuck on closed loop either. BTW I think the high-pressure switch on these cars only operate half speed using resistor R-15. I've bridged a few in the past as a temporary fix due to a faulty switch.
[Edited by vinamg on 04-18-2001 at 09:58 AM]