My wifes pontiac grand prix has wiper issues. they only want to turn on when they are in the fastest mode

I have seen 2 options on the grand prix. First check ground strap by wiper motor............[under cowl cover]. Second would be your combination switch on steering column. ie turn signal. headlamp high low etc.

Wiper pivots need to be replaced !

replace the arm it's self. take the streering wheel..

You can try disassembling the wiper arm selector switch (mounted inside the steering column) and cleaning up the contacts with contact cleaner and/or repositioning the contact tabs. If that doesn't work, then a new wiper multiswitch is what it needs.

You need to turn wipers off, then remove wiper arms and reposition them to the off (down) position. Retighten them and you should be good to go.

The intermittent function for the wipers has a variable resistor that controls the timing of the wipers in this mode. Replacement of the wiper switch will resolve this issue. Over time they do become worn, and do not make contact during the entire wiper cycle.

If you have just changed the wiper arms, they may not have been reinstalled correctly.....hoever if it has just started happening,,,,,???

unfortunately this is a wiper motor fault....not the switch.......inside the motor is a PARK function.....this is where the wipers will stop after doing a swipe across the windscreen and the switch is turned off.........this park function is a section inside the motor that cannot be removed and replaced internally, and it would cost more than just a replacement wiper motor

Good luck and i hope this helps...
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needs wiper module. check bushings around wiper motor at the firewall.

The wiper arms are mounted to "splined" shafts. Either the arm or shaft may be stripped. You need to remove the arm and inspect them.