windsheild wipers only operate on the fastest speed. on 2004 Hummer H2

windsheild wipers only operate on the fastest speed. all speeds were working yesterday. does the motor did replacing? Where can I obtain step by step instructions to replace? Many thanks.

by in Seven Valleys, PA on September 09, 2011
1 answer
ANSWER by on September 11, 2011
Step by step instructions will be in a repair manual that you may be able to get online or likely at a parts store. The rheostat that controls speeds is likely bad. It is a progressive resistance circuit that builds ohms resistance to control the speed. May be a seperate part or in the motor or a prob with the speed control in the vehicle.