Engine Cooling problem
1997 Chevy Lumina 6 cyl Front Wheel Drive Automatic
The engine cooling fans do not operate at elevated coolant temperature levels. To run the fans I have to switch the climate control to A/C to bring the temperature down. If I disconnect the coolant temperature sensor on the engine block the fans will run regardless of the coolant temperature.
Is this an ECM problem, if so how can I cure it?
It's not a problem at all. Those fans are even programmed to come on before about 225 to 227 which seems real high but that is how they work.
November, 4, 2010 AT 7:16 PM
The fans don't run even when the temperature gauge is in the 'red' zone.
I wouldn't have submitted the question if I thought that the answer was that simple!
November, 4, 2010 AT 7:23 PM
It's not the first time I have run across the situation, in fact I see the question quite often when there is nothing wrong. Every one of them thought they had a problem also. By unplugging the sensor and initiating the fan operation you have proven that the entire circuit is fully function able and the PCM has full control of the fans. The PCM uses the same coolant temp sensor for these decisions as it uses for all the mixture, timing and idle speed decisions so I doubt there is any problem there. The only thing that may be possible is that the temp gauge on the dash is inaccurate and reading higher than it should since it uses a different sensor.