Driver side wiper doesn't work

SOURCE: windshield wiper

Check to see if the wiper motor moves the passenger side. If so, You may need to tighten the nut that connects the arm to the motor. Mine was stripped out because or snow & ice. So, I went to home depot and found a lock washer to fit.
Presto.... Nick from DE

SOURCE: Driver side wiper doesn't move on 2006 Mazda 3

thers a bolt where the wiper piviots and it might need tigting

SOURCE: my driver side windshield wiper

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. 

SOURCE: windshield wiper on driver's side of Hyuandi doesn't work -

I recently had the same problem of the drivers side wiper not working. My boyfriend (a mechanic) took the windshield cowl off and looked to see what was going on. He originally thought that maybe something had slipped off. I'm going to describe what he found in layman's terms. When you take off the wiper blade arms from the wiper transmission assembly unit there are these silver colored nubs with grooves on them (one for each wiper). What he found was that on mine the grooves were stripped so that the wiper on the drivers side wouldn't catch and go across the windshield while the other wiper worked fine. What we think that happened is that I left the wipers on when I shut off the car and since we had a huge snowstorm the wiper transmission bound up and stripped the nubs when I turned on the vehicle the next day and let it warm up. I had tried for the past week to find a used replacement wiper transmissions assembly but was not successful. I just ordered the part from my local Hyundai dealer at a cost of $180. I will at least save on the labor, as my boyfriend can handle that part. If you try to get the part used, be careful. There was a product change mid-year. Prior to June 2004 (If I remember correctly) is one part number and Santa Fe's manufactured after that date is a different part. I needed the earlier Santa Fe part. You can look at the body panel between the front and back doors on the driver's side for the production date of your vehicle there is a metal decal with the vin, your color codes, and other information.

SOURCE: 2002 Chevy Tahoe-Drivers Side windshield wiper not working

There is a bar that connects both your windshield wipers together check that to see if it is broke or has come unscrewed. Should be underneath the hood upagainst the firewall.

Testimonial: "Thank you. That was the problem the bolt was loose"