Windshield wiper on 1998 c230 stopped working when trying to clear heavy snow from windshield. then it was pushed all the way down to the right hand side of windshield and now cant budge it

Could be loose wiper arm. Are the blades heavy. Too big of wiper blade will cause problems

The windshield wiper circuit has an circuit breaker in it, under heavy load this breaker trips to protect the wiper motor, when the motor cools, the breaker resets automatically restoring proper wiper action.

ARE YOU BLIND?

the pivots that hold the wiper arm are probaly stripped or one of the arms have come off

a screw is missing from the part u attatch the whper to

see if the transmission arms for the wiper motor are moving when the wiper motor is on. The bolts that hold the arms to the motor may be loose or stripped out from the heavy know. The threads for these bolts are thin and don't take much to strip.

You should check your fuses first. What may of happened is that the wiper motor could be frozen if the wiper arms are frozen in ice. Another thing that may of happened is that the wipers were used to clear the windshield instead of clearing it manually. When that is done if there is too much snow or it is a heavy snow the wiper motor will burn up or go bad due to the fact that it does not have enough power to do such things.

If the wipers were buried under snow/ice or frozen to the windshield, you may have blown the red 10 amp fuse located in cavity 9 in the fuse block located on the bottom left side of the instrument panel near the parking brake pedal.
In order of easiest to check:
1) ensure wipers not frozen to windshield.
2) ensure wiper arms are not loose on the pivot stud,
3) check the red 10 amp fuse.
You stated that "you can hear the motor". Which motor do you hear? The engine or the wiper motor?
If you hear the wiper motor, then the fuse is alright. Try 1) and 2) above.
PT Stanley

I just solved this problem last night with my '05 Impala, and ultimately the solution was what newton5083 stated above.  Yet, it may also be this (I found it online somewhere):
You have bent or broken the "park tab" on the windshield wiper motor bracket. The correct way to fix this is to remove the wiper arms, wiper linkage and wiper motor from the wiper motor bracket, and install a new bracket.
I just bent the tab back into place a couple times for our daughters 2005 Impala but it kept getting bent down again when they didn't take the time to make sure the wipers were not frozen to the windshield, or tried running the wipers to remove heavy snow on the windshield. So yesterday I fabricated a small piece of metal and bolted that to the bracket in the same place the tab stop was.
If someone wants to access this bracket and tab-
1. Use a ½ inch or 13mm socket & ratchet or wrench to remove nuts on wiper arms.
2. They may make a special tool to remove the arms, I used a screwdriver and hammer to tap bottom of the arm to wedge them apart from the spindle.
3. Two small button-looking clips hold the drivers side cowl cover in place under the windshield. These are two-piece clips, pry up the center, than the outer piece.
4. Unclip the washer hose from cowl cover, than pull out plastic cover.
5. There is a smaller plastic cover with on plastic button head holding that cover in place. Gently pry under that clip to remove that cover.
6. Now you can see the wiper trans and bracket. You should see a small tab on that bracket that looks pushed down and bent or possible a square small hole with some torn off metal where the tab broke off.
7. Remove small plastic cover over the wiper transmission and you can see a small spring-loaded arm underneath the wiper transmission assembly.
8. You need to find something to pry that tab back up so when the wipers are running that spring loaded little arm just snaps past the tab running clockwise. It's when you shut off the wipers that the wiper transmission assembly reverses rotation counter clockwise and the small spring loaded arm underneath hits that tab stop, than the wipers will go all the way down and shut off as they should.
Once that tab stop gets bent out of the way the little spring loaded arm has nothing to stop the wiper transmission assembly so it keeps traveling counter clockwise until some other stop shuts the wipers off straight up on the windshield.

There is a revised bracket part # which is supposed to be more durable, GM part #12368639. Here is a copy of the TSB which points out this problem:
Bulletin No.: 05-08-43-003A
Date: March 10, 2005
TECHNICAL
Subject:
Windshield Wipers Park in Up Position (Replace Windshield Wiper Motor Bracket)
Models:
2005 Chevrolet Impala, Monte Carlo
Supercede:
This bulletin is being revised to make a correction to the Parts Information. Please discard Corporate Bulletin Number 05-08-43-003 (Section 08-Body and Accessories).

Condition
Some customers may comment that the windshield wipers park in the out wipe (vertical) position.
Cause
This condition may be caused by a bent park tab on the windshield wiper motor bracket.

Correction
To correct this condition, replace the wiper motor bracket. It will be necessary to transfer the following parts listed below to the new bracket.
^ Wiper transmission
^ Wiper motor crank arm
^ Wiper motor
1. Remove the windshield wiper motor drive system module.
2. Remove the windshield wiper transmission from the windshield wiper motor bracket.
3. Remove the wiper motor crank arm from the windshield wiper motor.
4. Remove the windshield wiper motor from the bracket.
5. Install the windshield wiper motor to the new bracket.
6. Install the wiper motor crank arm to the windshield wiper motor.
7. Install the windshield wiper transmission to the windshield wiper motor bracket.
8. Install the windshield wiper motor drive system module.

A TSB is not a recall, if vehicle is still under warranty the dealer should be repaired for free. If not, you'll have to pay for the repairs. 

there is a clip under the blade where  the arm that goes through the wiper blade is a tab that you need to press toward the arm until it releases
look for a tab.