I have replaced the resistor pack on my '05 at least three times. The last one lasted about three weeks. Soooo, I figured the blower motor was drawing too much power and changed that out, (it was squeaking anyway). Two days later, driving along, suddenly start seeing smoke coming out from under the dash!! Turned the fan off and it went away!! Got home, got under the dash, tried the fan...... nothing but high speed again.
Tried to pull the plug off the resistor pack, couldn't get it off! It welded itself right to the resistor pack.
I did get it off the resistor pack, completely melted the two outside connectors, wires were burnt an inch up from the connector.
The new harness has much larger wires than the original did.
Oh well, live and learn!