Wipers Operate On High Speed Only

Remove connector from wiper motor. Turn ignition on. Place wiper switch in LO position.
Using voltmeter, measure voltage from Gray wire of wiper motor connector to ground. If battery voltage exists, proceed to step 4).
If battery voltage did not exist, check for open in Gray wire between wiper switch and wiper motor. Check for defective connection at Gray wire of wiper switch. If all are okay, replace wiper switch.
If battery voltage exists, check for defective connection at Gray wire connection of wiper motor. If connection is okay, replace wiper motor.