Chevrolet Repair: heater blower only blows on high, chevy s10 pickup, s10 pickup

Question
hi Scott, i have a 1988 chevy s10 pickup..and the heater blower stopped running in the low and medium speed. it only runs in the high position..i changed the switch.because i thought it might be bad contacts in the switch.that didn't correct it .it still only blows on the high position..any suggestions would be greatly appreciated. thanks, john miller  

Answer
have you check the blower itself? that may be the only speed left its has.  check the wries, contacts, and the blower motor itself. im think the blower it self may ned replaced or grounded.  make sure to throughly check the whole system.  hope this help some.