High temperture The temperture readout has reached as high as 214 degrees when idling and the fan does not come on only if i turn the ac on or recirulation button. I have changed out the temperture sensor, relay and the installed a new fan/shroud. Does not read hot when running down the road only when idling, what could be the problem?

There is a temp sensor that tells the computer what the engine temp is - when it reaches 220 degrees the computer grounds the fan relay.
You would need to know if the relay has power and is getting a ground from the computer.

Did you check for voltage at the relay ?
The computer grounds the relay when engine temp reaches about 230 degrees or the ac high pressure is above 200.
Can you jumper the relay contacts to make the fans run ?

Your electric fan should come on around 220 degrees or so, if it does not you need to replace the sensor on the left front side of the block. The fan should come on immediately if you have AC and turn it on. If it does not check the relay in the fuse box under the hood, and related fuses. Unplug the electric fan and turn the ac on and check for power. It could be your fan motor quit. Usually if the fan does not come on when the AC is turned on, and it does not come on when car reaches 220 degrees, the motor is most likely the culprit.

Hello: When setting at idle in park the fan should come on when the coolant temp reaches approximately 236 degrees F. Just let the car set and idle to check and see if they come on. The fans do NOT run continuously when the A/C is off.

Sure the engine coolant will be warmer than the outside temperture and if the car has been sitting a long time in cold weather and the outside temperture warms up it could be the other way around. The coolant temperture sensers aren't real accurate as they are a relaitive senser beween hot and cold and the numbers reported don't have to be real just the change from hot to cold and the reching of the coolant to the operating temperture. Noe it the senser doesn't read the opertating temperture coprrectly you'll have all kinds of problems. The therostaste will try to set the temperture of the water to it's set temperture and can open or close completly to get 195 degrees F. Many times if it's too cold then the stat is bad and needs to be replaced This shows up in alot of cars first thing after winter and the first onset of cold weather when the daily tempertures vary the most from day to night.

Instrument cluster - GM had problems with a part inside the cluster , Stepper motor , These faulty step motors caused the gauges to act erratically . 2003 to 2006 ! ALL GM vehicles . Just replaced a cavalier instrument cluster for what customer thought was a over heating problem .The fans come on low speed when engine temp. reaches 220 degress
The PCM commands the low speed cooling fans ON under the following conditions:
• Engine coolant temperature exceeds approximately 104.25°C (220°F).
• A/C refrigerant pressure exceeds 1447 kPa (210 psi).
• After the vehicle is shut OFF if the engine coolant temperature at key-off is greater than 101°C (214°F) the low speed fans will run for a minimum of 60 seconds After 60 seconds, if the coolant temperature drops below 101°C (214°F) the fans will shut OFF. The fans will automatically shut OFF after 3 min. regardless of coolant temperature.
The PCM commands the high speed fans ON under the following conditions:
• Engine coolant temperature exceeds approximately 107.2°C (225°F).
• A/C refrigerant pressure exceeds approximately 1824 kPa (265 psi).
• When certain DTCs set.
At idle and very low vehicle speeds the cooling fans are only allowed to increase in speed if required. This insures idle stability by preventing the fans from cycling between high and low speed.

there are 3 cooling fan reays in a 98 aurora and they are computer controlled. the low speed fan relay should turn on when the ecu detects a temp of 229 degrees and should turn off when the temp has dropped to 216 degrees. it is best to check the temp with a computer monitor so you can see what the computer is reading. If you turn the a/c on you can see if the fans are operating. If they don't come on with the a/c you may have a problem with the high side a/c switch. A bad thermostat can cause the fans to come on late.

The cooling fans on this vehicle won't come on unless the a/c is on or until the engine coolant temperature reaches about 220 degrees. Once the coolant has reached this temperature the fans will come and and run until the engine cools down to about 210 degrees and they will then turn off until the temperature climbs up again. The fans usually aren't on at all at highway speeds because enough air is being forced through the radiator to keep everything cool. The true test of cooling fan operation is to allow the car to idle in park with both the a/c and defrost turned off and let it run until the fans come on. When The temp gauge reaches about 3/4 of the way up, give or take a bit, the fans should come on. Keep an eye on the gauge so the engine doesn't overheat just in case there really is a fan control problem but I'd say you'll most likely find that the fans are working properly since they do come on for the a/c. Hope this helps!

the engines electric cooling fan is not designed to come on when u start the car, it only runs when the engine temp reaches about 225 degrees F, this only occurs after long idle times or very hot weather..

you need to make sure the cooling fans are turning on when it reaches 212 degrees,it could be a blown fuse for coolant fans or a relay