1993 Chevy Suburban windshield wipers

Wipers Run At High Speed Only 1. Disconnect wiper motor connector. Turn ignition to ACC position and wiper switch to LO position. Connect test light between ground and Gray wire terminal of wiper motor connector. See Fig. 2 . If test light comes on, replace wiper motor (replace delay module on pulse system). 2. If test light does not come on, connect test light between ground and Gray wire terminal of wiper switch connector. If test light does not come on, replace wiper switch. If test light comes on, repair open in Gray wire between wiper switch and wiper motor. Also the circuit boards on the motor are replacable, and solve most wiper problems. It's called the pulse module.