blower speed control problem

i'm having the opposite problem most people are experiencing with their blower control that all speeds work EXCEPT high. most people seem to lose their lower fan speeds first for which the fix is a blower resistor replacement. if all speeds but high work is it then a blower relay malfunction? the high setting will start out at times but then cut out. also my wife claims it won't work if the rear blower is also on high. any ideas?

since posting my research might indicate on the montana that the resistor and relay are combined in 1 unit. my other vehicle (94 safari) has separate resistor and relay. is this the case?

i've been able to answer my own question. further research has shown me that the blower resistor and relay are combined into one unit and replacing it will resolve all blower speed issues.