Mechanics

COOLING FAN RUNS WITH COOLANT SENSOR DISCON

1997 Saturn SL2

Engine Cooling problem
1997 Saturn SL2 4 cyl Front Wheel Drive Automatic 205000 miles

over heating warning light on consistantly. Cooling fan was not running. Replaced coolant temp sensor. Cool fan is still not running. But is running with coolant tem. Sensor discounted. HELP! Is my car possessed. It is Halloween. Scary. LOL
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Eric gauch
October 31, 2010.




When you replaced the coolant temp sensor did you inspect the coolant temp sensor for being corroded?If it's corroded you have to replace the connector. Also you said your overheating light flashes how high is your temp gauge getting?Have you checked your coolant level?If it's low that light will flash. Let me know what you find.

Saturntech9
Oct 31, 2010.
The coolant temp sensor has been replaced and there is no corosion on the connector. Whats interesting is the cooling fan will run continuosly with the temp. Sensor disconnected. The coolant level appears to be where it needs to be. The coolant temp. Warning indicator is flashing on the instument cluster. I started diagnosing the problem as a inop. Cooling fan and by the tree it points to the PCM being the problem, I'm not a 100% sold on this being the problem area? Any ideas? Thank you

Tiny
Eric gauch
Oct 31, 2010.
If you unplug the coolant temp sensor then the fan will run all the time the computer goes into a fail safe mode to protect the engine from overheating by running the fan all time. Fill the coolant bottle up to the seam of the bottle and see if light turn's off. Also if you let the car idle with the sensor plugged in what temp on the gauge does the fan come on at?
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Saturntech9
Oct 31, 2010.
Ok, I have checked to see that the coolant level is at the seem in the resivor, the coolant sensor has been conected. I noticed that the temp gauge is at approx. 1/4 gauge and climbing, the temp warning light is flashing and the cooling fan is still not coming on?

Tiny
Eric gauch
Oct 31, 2010.
Let it idle the fan will come on at about just over half way on the gauge. Let me know if it come's on. Also check your back up light fuse in your under hood fuse box.

Saturntech9
Oct 31, 2010.
Ok, the cooling fan came on between 1/2 and 3/4 on the gauge. I checked the back up lamp fuse and its hot on both sides. The warning lamp continues to flash in the cluster. Yet the coolant is at the seem in the resivor?

Tiny
Eric gauch
Oct 31, 2010.
Ok your fan is working correctly now your going to have pop up your coolant bottle and unplug the connector to it then use a wire to jump the two terminal's together and start your car and see if your light turn's off.

Saturntech9
Oct 31, 2010.

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