Check the Technical Library on this Ranger Forum. Under Heater/A/C Trouble Shooting - Blower Motor Replacement Issues. It describes exactly what is wrong when ONLY the high speed operates on the A/C blower. It will be the resistor (was on mine anyway) which on mine ('92 Ranger) was located in the heater housing just to the right of the blower motor under the hood to the left of the engine. There is a wiring harness plugged into it and 2 screws holding it into the heater housing, Remove and check for "junk" inside like leaves which on mine caught fire. Yep, had "smoke on the Ranger". Scared the bejabbers out of me, so much so that I stripped the On/Off knob for the Heater/A/C getting it turned off. New resistor at auto supply was only $15.95 which I installed myself. I don't see that the cowl vent holes are large enough to let whole dried leaves into the air intake system thus into the heater core area. Can anyone explain just how the leaves got into the heater housing?
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