service bulletin number 08-31-98 Rev. A issued on Jul. 24, 1998 titled: "Front Wipers - Self Activate Or Won't Turn Off" this might help. Some people say it is just the wiper control on the steering column that needs replacing, and some say it could be corroded wires at the fuse panel// which can be cleaned with electrical cleaner. I havent tried it on mine.
A bad relay switch will cause the windshield wipers to not turn off. Replace the relay switch and the windshield wipers should turn off.
switch them on
There is no button to operate the headlight wipers. The headlights washers and wipers are activated along with the windshield wipers when you use the windshield washer by pulling the wiper switch towards you.
remove the wipers, turn on wiper switch, turn off switch, reinstall wipers @ bottom position torque nuts enough to secure the arm. turn on switch readjust as needed.
The windshield wiper relay switch can be found on the firewall in the engine compartment. The windshield wiper relay switch will be on the passenger side of the firewall.
A bad fuse may be the cause of windshield wipers not working on a 1998 Lumina. The switch that activates the wiper motor is another possible cause for the wipers not working.
Windshield wipers don't work
under the hood by the engine
Why are there windshield wipers inside the car?
It sounds like the switch has gone bad allowing the wipers to run constantly. Have the windshield wiper switch replaced.
check the wiper fuse. then check the switch, then check the wiper motor
If the windshield wipers work when pushing the lever down but not when they are turned on all the time, the problem could be in the wiper motor relay switch. There are two different relay switches for the windshield wipers, so that if the one fails a person can still clear the windshield manually.