I have a Harbor Breeze (Builders Series) ceiling fan. It appears that the speed control reastat is defective. I removed the wall switch to determine if that was the problem and it is fine. What I would like to do is eliminate the built in reostat in the fan altogether. I have purple, black, grey and brown wires coming out of the pull chain switch and going into the reostat. I have a red wire that comes out of the reostat and connects to the red wire for the fan, I also have a grey wire that goes to the reversing switch. I disconnected the purple and brown wires but still only have 2 speeds. Any help would be greatly appreciated.

How many wires on rheostat? if 2, disconnect rheostat, connect the 2 wires?
If you are talking about pull switch, switch may be bad.
Do you want max out of fan without pull switch, then black, from power to brown that was disconnected, would be best guess, need to reconnect purple and brown.
How many wires on rheostat?

I'm very confused.

1. How many wires go to the wall control?
2. Are you talking about the 'reostat' in the wall or the one in the fan?
3. If the problem is with a wall control, why are you opening up the fan?

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Strat, to max out the fan, you would connect black and grey.

Just removed from working fan, sounds like yours.
The Black(Fan power in goes to L, L3 is Gray wire and goes to motor gray, L2 is Brown wire, and goes to motor brown, Purple(L1)goes to center of reverse switch, the other center of the DPDT switch goes to neutral, and to those 2 neutrals you need to connect to
White of 4.5 mfd? Capacitor, out of that capacitor is red wire and goes to motor red.
The reverse switch has 2 yellows, they go to motor yellow. And 2 oranges connect to motor orange, with the orange and yellow connected to opposite corners of direction switch, is like a polarity switch.
Does this sound close?
I was assuming fan goes High, Medium, Low(1,2,3)

In all the fans I've seen, grey and purple are reversed from what you just said. What fan do you have?

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