AC with fan on 4 keeps changing speed, mostly blows low, if I hit a bump it will sometimes kick on high for less than a minute. Also the control unit goes off completely than comes back on. Is there a relay somewhere?
I don't think its a relay problem.
I think the problem is between the upper and lower circuit boards in the A/C heater control unit.
If you have a friend thats in to computers he may be able to find the broken connector in the control unit and repair it for you.
The other fix would mean spending the big dollars on a new control unit. BW