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Q: AC only working at lowest speed

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The AC works only at the lowest fan speed. It does not work when the fan speed is increased.

Hello! We will be happy to help. If the AC is blowing cold on one speed but does not on others it leads me to believe that that AC system itself is working properly. Therefore, I would look more towards AC system control to find the problem. A common issue that causes your concern is a faulty blower motor resistor pack. I suggest that a technician test the electrical resistance at the resistor pack at each speed. All resistance readings should be within specification. If they are not, the replacement of the cooling fan resistor pack is suggested.

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