Engine Fan Running all the time

Greetings,

I have a 1989 Buick lesabre 3.8 vin c. The Engine fans runs as soon as the car is started. The car is giving me code 15 indicting low voltage on the coolant temp sensor. The pick tail coming from the computer is providing the correct voltage of 5 volt so that is a bogus code. and i replaced the sensor with a Napa one. But the fan keeps running. I also replaced the computer 2 twice with a Nape unit. I checked for exposed and broken wires. I NEED HELP to get my car fan operating properly!!! If you have a GM Tech 1 for sale lets talk. Thanx for your help.

Could it be a stuck on Relay?

I replaced the relays a few weeks ago and it keeps running.

Is the thermo sensor for the electric fan located on the radiator?

This car has one on the engine block and a ceramic temp switch on the fan itself.

The ceramic coated block on the fan is likely a resistor for low fan speed.

The fan is running because of the temp sensor code set- you need to concentrate on engine temp sensor circuit- get to a Tech I and see what temp the computer thinks the engine is....