My windshield wipers do not work properly. Examples: when you push the lever down, for 1 time, it sometimes goes 18 times before it stops. When it is on the interval option, it stutters. I had my multi-function switch replaced to fix the clicking and it sorta helped the windshield wipers. Since this was repalced, the horn no longer works.

Have you lined up the wipers properly on the windshield? There’s a small black line on the windshield that helps you to line up the wiper arms when you reinstall them on the drive spurs. That may be the issue. If you’ve changed the wiper motor and not messed with the wiper transmission, the timing could be off. If the wiper motor is slotted into the wiper transmission, it may be clocked 180 degrees off, giving you the issue.

WHEN I START MY MERCEDES C- 180 MODEL 1997 YHE SRC LIGHT REMAIN ON AND THE AIR BAG LIGHT DOES NOT COME ON , HOW EVER IF I USE DIPPER OR WIPER BOTH DOES NOT WORK INSTEAD THESR LIGHT FLIERS WHEN WIPER LEVER IS PLACED ON OR THE LIGHT GOES OF TILL THE TIME DIPPER SWITCH IS PRESSED

sounds like the connecting rod between both wiper arms either broke or one of the keepers popped off under the connector for that arm..since the wiper system IS NOT designed to wisk snow off the window once accumulated, this can an does happen.. even seen motors get burned out doing this..cleaning the window first will save this issue and the equiptment. need to acess this arm<take off the vented peice below the windshield and everything should be visible there..repost findings

At the base of the wiper arm there is a plastic cap,pop this off ,underneath there is a nut that holds the arm in place ,if it gets loose the post will turn inside the blade.Just turn the wipers off and tighten the nuts with the blade in the parked position.

it sounds like the transmittion in the wiper motor is not working right. check it and probably replace the wiper motor

Windshield Wipers Not Working - Things to Check
To troubleshoot car windshield wiper problems, you need to thoroughly investigate problems with any of its operating parts. Here are some of the things that you need to check to determine why are your car windshield wipers not working.
Check Wiper Motor
The wiper motor is the driving force of the windshield wiper. Feel the motor and listen to a humming sound. If there is no humming, the motor is the problem. Check if the motor is working properly and see to it that its electrical connections are made properly. If you find that the motor is dead and beyond repair, get it replaced immediately.
Check For Break in Connecting Wires
The connecting wires of the motor sometimes go loose and that may cause the windshield wipers to stop working. Also check the battery plug connection which the motor has. Connecting the loose wires properly or fixing/replacing the plug might solve your problem.
Check Wiper Switch
Another wiper assembly part that can malfunction is the wiper switch itself. Check for switch malfunction and if you find that is indeed the problem, get it replaced from a mechanic.
Check for Bent Wiper Arms
Bent wiper arms can cause the operation of the wipers to be hampered. If the wiper arms are bent beyond repair, get them replaced immediately.
Check For Blown Out Car Fuse
A blown up car fuse could be the culprit that has stopped the windshield wipers from working. Check the fuse assembly under the dashboard of the car. Replacing a blown fuse might fix the problem of windshield wipers not working.
Windshield Wiper Sprayers Not Working - Things to Check
Sometimes the windshield wiper sprayer stops working which can be very annoying. The washer mechanism is a self cleaning mechanism for the windshield. Here are some of the things that you need to check in case it is not working.
Check Windshield Washer Motor
The windshield washer mechanism might have been impaired due to the malfunctioning of the wiper washer motor. Check if its working and get it replaced if it is beyond repair.
Check Windshield Washer Fluid Level
Sometimes the washer doesn't work because the washer fluid levels are not filled to requisite levels. Filling in fluid might restore normal functioning.
Check For Broken Washer Hose
The connecting washer hose that connects the reservoir to the nozzle, might be broken or worn out stalling the overall operation. Check the hose for leaks and get it replaced.
Check Washer Nozzle For Clogging
Last thing to check is the nozzle of the washer for clogging. An obstruction in the washer nozzle might be the reason for windshield wiper sprayers not working. Using a pin, clean the clogged nozzle. This might restore the sprayer to the normal working condition.

It has auto wiper control. Yank your wiper stick 1 notch down. The windshield should be free of rain droplets or else it would think it is still raining and operate it in auto mode. In auto mode it will shut off when it doesn't sense rain droplets on the windshield or removing the key from the ignition. Once it is off, it can only operate in auto mode by moving the lever 1 notch up while raining. Yours must be in the 1st speed manual selected position of the lever. Every time the ignition is switched on the wiper operates regardless until key is removed from the switch.

2002 Ford F-250 Windshield Wiper Motor Removal & Installation 1. Turn the ignition switch to the ON position. Turn the ignition switch ON until the wiper blades are straight up, then turn the ignition switch OFF. 2. Disconnect the negative battery cable. 3. Remove the right-hand and left-hand windshield wiper arm and blade assemblies. 4. Remove the cowl top vent panels. 5. Detach the electrical hardness connector at the windshield wiper motor assembly. 6. Remove 3 wiper motor (module assembly) retaining bolts and remove the module assembly from the vehicle. 7. Remove the wiper linkage retaining bolt and remove the linkage from the wiper motor. 8. Remove 3 retaining nuts and remove the windshield wiper motor To install; 9. Place the windshield wiper motor in position and install 3 retaining nuts. Tighten to 10-12 ft. lbs. (12-17 Nm). 10. Connect the wiper linkage to the windshield wiper motor and install the retaining bolt. Tighten the bolts to 14 ft. lbs. (20 Nm). 11. Place the wiper motor (module assembly) in position and install 3 retaining bolts. Tighten the bolts to 6 ft. lbs. (9Nm). 12. Install the electrical hardness connector to the windshield wiper motor. 13. Connect the negative battery cable. 14. Allow the windshield wiper motor to cycle several times while checking for proper wiper motor operation. 15. Turn the windshield wiper motor to the OFF position to park the wiper motor in the park position. 16. Install the cowl top vent panels. 17. Install the wiper arm and blade assemblies. Install the retaining nuts and tighten to 22-29 ft. lbs. (30-40 Nm). 18. Connect the negative battery cable. 19. Check the windshield wiper motor for proper operation and the wiper arms for adjustment.

If your'e just removing the wiper blade, check for a "release lever" where the wiper attaches to the arm, push (or pull) the lever and pull down on the blade at the same time. Do the opposite to install, except you do not have to push the release lever.
If you are removing the whole arm, there is a special tool that you slide under the arm that releases it from the 'gear'.

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.