Windshield wipers on my 05 impala work when they are on higher speeds but when I turn them down they stay up on my windshield. When I turn them off they stay down. Can it be the leakage?

Just replacing parts isn't the way to fix this problem , viewing wiring diagrams too see what all is involved in making the wipers work is . Then using a digital volt ohmmeter to test electrical circuits . Also looking at factory service info. to see how it's suppose to work.
Free wiring diagrams here http://www.bbbind.com/free-tsb/ Enter vehicle info. year , make , model an engine size . Under system click on body & accessories , then under subsystem click on wiper/washer . Click the search button ,then click the blue link. Looking at the wiring diagram i see two fuse's an two relays that are controlled by the BCM - body control module . Also hooking up a scan tool that can read BCM DTC'S - diagnostic trouble codes could be helpful . The wiper switch is a input to the BCM - the BCM will energize the relays to turn on the wipers.

Wiper/Washer System Components
The Wiper/Washer System consists of the following components:
• Windshield wiper/washer switch
• Body control module (BCM)
• Wiper 1 relay
• Wiper 2 relay
• Wiper diode
• Windshield wiper motor
• Windshield washer pump
• Windshield washer nozzles
• Windshield washer solvent container
• Windshield wiper arm and blade assemblies
• Windshield wiper transmission
• WIPER/SW 10A fuse
• WIPER 25A fuse

Wiper/Washer System Description
The body control module (BCM) controls wiper motor low speed operation. The washer pump and high speed operation are controlled directly by the wiper/washer switch. The windshield wiper/washer switch supplies voltage on the signal circuits to the BCM for windshield wiper/washer operation. When WASH, MIST, DELAY, LOW, or HIGH is detected, the BCM energizes the wiper 1 relay by suppling voltage to the relay coil. This allows battery voltage from the WIPER fuse to flow through the relay switched input then through the contacts and out the relay contacts to the wiper 2 relay switch contacts. Since the wiper 2 relay switch contacts are normally closed to the low speed circuit of the windshield wiper motor, the motor will operate at low speed.

DTC B3715 02: Front Wiper Relay Drive Circuit Short to Ground
DTC B3715 05: Front Wiper Relay Drive Circuit Short to Battery or Open

You didn't take into account the wiper switch is a input to the BCM - body control module ,or do you know that ? The BCM controls wiper one an wiper two relay's to turn on the wipers .
Wondering if it is the PCB or perhaps a physical problem? Guessing never finds the problem . Reading how they work in factory service repair info should be the first step for someone that doesn't know .
Intermittent Operation
Windshield wiper DELAY operation is a low speed wiper motor function with a variable delay interval between the wiper motor cycles. The DELAY interval is determined by a series of 5 resistors within the wiper/washer switch. During DELAY wiper operation, the signal circuit voltage is further reduced through the DELAY resistors. The body control module (BCM) monitors the voltage on the signal circuit to determine the delay interval between the low speed wiper motor cycles.
If the wiper switch is moved from a longer delay interval to a shorter delay interval, the BCM will command an immediate wipe cycle and reset the delay timer to the shorter delay interval.
Additionally, intermittent wiper operation is vehicle speed sensitive. As vehicle speed is increased or decreased, the wiper interval will also increase or decrease.

Low Speed Operation
When the wiper switch is in the Low position, voltage is supplied through an internal resistor to the signal circuit. The body control module (BCM) monitors the windshield wiper switch signal 1 circuit and energizes the wiper 1 relay which will operate the windshield wiper motor. The wiper motor will operate at low speed, since the wiper 2 relay is de-energized. Low speed can also be commanded with a scan tool by commanding Wiper Relay Cmd. ON and OFF.
High Speed Operation
In the High position, the windshield wiper/washer switch supplies voltage to both the wiper 1 and wiper 2 relay coils. This energizes both relays and allows battery voltage from the wiper 1 relay switched output to the switched input of the wiper 2 relay through its contacts and out the switched output of the wiper 2 relay to the high speed circuit of the windshield wiper motor. The windshield wiper motor will operate at high speed. During HIGH speed wiper motor operation, the wiper switch signal circuit is at the LOW speed signal voltage, and the body control module (BCM) supplies redundant voltage to the wiper relay via the wiper diode.

Wiper/Washer System Components
The Wiper/Washer System consists of the following components:
• Windshield wiper/washer switch
• Body control module (BCM)
• Wiper 1 relay
• Wiper 2 relay
• Wiper diode
• Windshield wiper motor
• Windshield washer pump
• Windshield washer nozzles
• Windshield washer solvent container
• Windshield wiper arm and blade assemblies
• Windshield wiper transmission
• WIPER/SW 10A fuse
• WIPER 25A fuse
Refer to Master Electrical Component List.

DTC B3715 02: Front Wiper Relay Drive Circuit Short to Ground
DTC B3715 05: Front Wiper Relay Drive Circuit Short to Battery or Open

Your best bet , take it to a qualified repair shop.

Principles of Operation
The windshield wiper motor receive inputs from the following:

• multifunction switch
• lighting control module (LCM)
• ignition switch
• battery junction box (BJB)
• central junction box (CJB)

The following components are integrated into the windshield wiper motor:

• windshield wiper motor module
• high/low speed relay
• run/park sensor (Hall effect)
• washer pump relay

High Speed Windshield Wipers
High speed is activated when the multifunction switch supplies ground to the windshield wiper motor module inputs. The windshield wiper motor module then supplies ground to the run/park sensor and high/low relay coil, activating the relay with voltage supplied from the ignition switch (RUN/ACC) through the central junction box (CJB). When the windshield wiper motor module receives voltage from the run/park sensor, it removes ground from the run/park sensor, deactivating it. The windshield wiper motor continues to operate from voltage connected through the run/park sensor until the Hall effect senses the magnet in the motor. When the Hall effect senses the magnet in motor the windshield wiper motor returns to the park position, the internal run/park sensor grounds the windshield wiper motor module input and the windshield wiper motor module removes ground from the windshield wiper high/low relay coil, deactivating the high/low relay and windshield wiper motor. The windshield wiper motor module continues to cycle the windshield wipers until the inputs from the multifunction switch are changed from the high speed position.
Low Speed Windshield Wipers
Low speed is activated when the multifunction switch supplies a specific ground to the speed inputs of the windshield wiper motor module. The windshield wiper motor module then supplies ground to only the windshield wiper run/park relay coil, activating it. When the windshield wiper run/park relay is activated, the deactivated windshield high/low relay connects voltage to the windshield wiper motor low input activating the wiper motor. The windshield wiper motor module continues to operate the windshield wiper motor in the same manner as in high speed, but in low speed with the wiper motor connected to the low speed input.
Intermittent Speed Windshield Wipers
The intermittent wiper speed is activated with grounds controlled by the multifunction switch inputs to the windshield wiper motor module. The windshield wiper motor module then activates the windshield wiper run/park relay coil and switches voltage through the windshield wiper high/low relay. The high/low relay remains deactivated, supplying the voltage to the wiper motor low speed input and activates the windshield wiper motor. When the windshield wiper motor module receives the grounded input, the motor continues to operate until Hall effect sensors senses the wiper motors magnet, which turns off the run/park sensor output to the windshield wiper run/park software, deactivating the relay and disconnecting voltage to the wiper motor. The windshield wipers remain parked until the windshield wiper motor module completes a time-out and then repeats the intermittent windshield wiper cycle.
Washer System
The windshield washer is activated by the internal wiper motor module when it receives a ground from the multifunction switch between the washer input. Dependent on the correct ground, the internal wiper motor modules activates the windshield washer relay (internal) by grounding the respective relay coil. When the relay is activated, it connects voltage to the washer pump while the washer level switch provides ground to the washer pump.
Default Mode
The windshield wiper motor defaults to this mode when the run/park sensor does not sense the hall effect magnet inside wiper motor. This can be caused by obstruction of the windshield wipers or a binding linkage. The windshield wiper motor will continue to operate in a high/low speed condition for a period of 60 seconds.

Symptom Chart
Symptom Chart Condition Possible Sources Action

• The wipers are inoperative

• Multifunction switch
• Circuitry
• Ignition switch
• Windshield wiper motor

• Go To Pinpoint Test A .

Do you know how to test automotive electrical circuits using a factory diagnostic test procedure flow chart ?

PINPOINT TEST A: THE WIPERS ARE INOPERATIVE Test Step Result / Action to Take A1 CHECK CIRCUITS 65 (DG) AND 2025 (RD/YE) FOR VOLTAGE

• Key in OFF position.
• Disconnect: Windshield Wiper Motor C125.
• Key in ON position.
• Measure the voltage between windshield wiper C125 pin 5, circuit 2025 (RD/YE), harness side and ground; and between windshield wiper motor C125 pin 8, circuit 65 (DG), harness side and ground.
• Are the voltages greater than 10 volts?

Yes
GO to A2 .

No
REPAIR the circuit(s) in question. TEST the system for normal operation. A2 CHECK CIRCUITS 57 (BK) AND 676 (PK/OG) FOR OPENS

• Key in OFF position.
• Measure the resistance between windshield wiper C125 pin 6, circuit 57 (BK), harness side and ground; and between windshield wiper motor C125 pin 3, circuit 676 (PK/OG), harness side and ground.
• Are the resistances less than 5 ohms?

Yes
GO to A3 .

No
REPAIR the circuit(s) in question. TEST the system for normal operation. A3 CHECK THE MULTIFUNCTION SWITCH

• Disconnect: Multifunction Switch C202b.
• Carry out the multifunction switch component test. Refer to Wiring Diagrams Cell 149 for schematic and connector information.
  
• Does the multifunction switch pass the component test?

Yes
GO to A4 .

No
INSTALL a new multifunction switch. REFER to Section 211-05 . A4 CHECK CIRCUIT 57 (BK) FOR AN OPEN

• Measure the resistance between C202b pin 5, circuit 57 (BK), harness side and ground.
• Is the resistance less than 5 ohms?

Yes
GO to A5 .

No
REPAIR the circuit. TEST the system for normal operation. A5 CHECK CIRCUITS 56 (DB/OG), 58 (WH), 61 (YE/RD), AND 63 (RD) FOR OPENS

• Using the following table, measure the resistance between the multifunction switch C202b harness side and the windshield wiper motor C125 harness side:
  
  Multifunction Switch C202b Windshield Wiper Motor C125 pin 6, circuit 56 (DB/OG) pin 10, circuit 56 (DB/OG) pin 3, circuit 58 (WH) pin 11, circuit 58 (WH) pin 1, circuit 61 (YE/RD) pin 1, circuit 61 (YE/RD) pin 4, circuit 63 (RD) pin 9, circuit 63 (RD)
• Are the resistances less than 5 ohms?

Yes
GO to A6 .

No
REPAIR the circuit(s) in question. TEST the system for normal operation. A6 CHECK FOR CORRECT WIPER MOTOR OPERATION

• Disconnect all wiper motor connectors.
• Check for:
  • corrosion
  • pushed-out pins
• Connect all wiper motor connectors and make sure they seat correctly.
• Operate the system and verify the concern is still present.
• Is the concern still present?

Yes
GO to A7 .

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation. A7 CHECK THE WINDSHIELD WIPER MOTOR

• Key in OFF position.
• Disconnect: Windshield Wiper Motor C125.
• Carry out the windshield wiper motor component test as outlined in this section.
• Does the windshield wiper motor pass the component test?

Yes
The system is operating correctly at this time. The concern may have been caused by binding or incorrect pivot arm adjustment. REFER to Windshield Wiper Blade and Pivot Arm Adjustment in this section. TEST the system for normal operation.

No
INSTALL a new windshield wiper motor. REFER to Windshield Wiper Motor in this section.

Depending on what your trying to do with wipers, I'd want to see voltage on the gray and or purple wire. See the black wire at the bottom that is ground, a good ground is a must. Hey Jeff, I'm not trying to bug you. If I spend time trying to look up info, I'm going to post it. I don't care if the question has already been answered. Have a good day.

You mean wiper arm ? Probably broken wiper arm linkage bushing you can't see , under the cowling . Can you move the passenger wiper arm up an down without much effort ? An not the drivers side ? To see it or get at it you would need to pull wiper arms off an take cowling off to get at it . How To Install Replace Wiper Motor 2000 05 Chevy Monte Carlo Impala How To Fix Broken Wipers EricTheCarGuy

Replace the wiper motor. It is under the wiper blades. remove the blade arms, remove the plastic bezel, remove the motor. The motor has the delay and speeds built in it.

Intermittent Speed Windshield Wipers
The intermittent wiper speed is activated with grounds controlled by the multifunction switch inputs to the windshield wiper motor module. The windshield wiper motor module then activates the windshield wiper RUN/PARK relay coil and switches voltage through the windshield wiper high/low relay. The high/low relay remains deactivated supplying the voltage to the wiper motor low speed input and activates the windshield wiper motor. When the windshield wiper motor module receives the grounded input, the motor continues to operate until Hall effect senses magnet to turn off RUN/PARK sense the output to the windshield wiper RUN/PARK software, deactivating the relay and disconnecting voltage to the wiper motor. The windshield wipers remain parked until the windshield wiper motor module completes a time-out and then repeats the intermittent windshield wiper cycle.

• The intermittent windshield wiper speed does not operate correctly

• Multifunction switch.
• Circuitry.
• Windshield wiper motor.

• Go To Pinpoint Test D .

Pinpoint Test D: The Intermittent Windshield Wiper Speed Does Not Operate Correctly
Normal Operation During normal operation, the windshield wiper motor receives voltage at all times through battery junction box (BJB) fuse 1 (30A), circuit 65 (DG). The windshield wiper motor also receives power with the ignition switch in RUN or ACC positions through central junction box (CJB) fuse 33 (15A), circuit 1002 (BK/PK). Ground is provided to the windshield wiper motor through circuit 676 (PK/OG) and circuit 57 (BK). The run/park and high/low relays are contained in the wiper motor electronics. Mode of operation is dependant on the signal(s) received from the multifunction switch.

Possible Causes
• Multifunction switch
• Open in circuit 57 (BK), 56 (DB/OG), 61 (YE/RD) or 63 (RD)
• Windshield wiper motor

PINPOINT TEST D: THE INTERMITTENT WINDSHIELD WIPER SPEED DOES NOT OPERATE CORRECTLY Test Step Result / Action to Take D1 CHECK THE MULTIFUNCTION SWITCH

• Key in OFF position.
• Disconnect: Multifunction Switch C202b.
• Carry out the multifunction switch component test. Refer to Wiring Diagrams Cell 149 for schematic and connector information.
  
• Did the multifunction switch pass the component test?

Yes
GO to D2 .

No
INSTALL a new multifunction switch. REFER to Section 211-05 . TEST the system for normal operation. D2 CHECK CIRCUIT 57 (BK) FOR OPEN

• Measure the resistance between multifunction switch C202b-6, circuit 57 (BK), harness side and ground.
• Is the resistance less than 5 ohms?

Yes
GO to D3 .

No
REPAIR the circuit. TEST the system for normal operation. D3 CHECK CIRCUITS 56 (DB/OG), 61 (YE/RD) AND 63 (RD) FOR OPENS

• Disconnect: Windshield Wiper Motor C125.
• Using the following table, measure the resistance between multifunction switch C202b harness side and windshield wiper motor C125 harness side:
  
  Multifunction Switch C202b Windshield Wiper Motor C125 Pin 2, circuit 56 (DB/OG) Pin 10, circuit 56 (DB/OG) Pin 4, circuit 61 (YE/RD) Pin 1, circuit 61 (YE/RD) Pin 1, circuit 63 (RD) Pin 9, circuit 63 (RD) Pin 3, circuit 58 (WH) Pin 11, circuit 58 (WH)
• Is the resistance less than 5 ohms?

Yes
GO to D4 .

No
REPAIR the circuit(s) in question. TEST the system for normal operation. D4 CHECK FOR CORRECT WIPER MOTOR OPERATION

• Disconnect all wiper motor connectors.
• Check for:
  • corrosion.
  • pushed-out pins.
• Connect all wiper motor connectors and make sure they seat correctly.
• Operate the system and verify the concern is still present.
• Is the concern still present?

Yes
GO to D5 .

No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. TEST the system for normal operation. D5 CHECK THE WINDSHIELD WIPER MOTOR

• Key in OFF position.
• Disconnect: Windshield Wiper Motor C125.
• Carry out the windshield wiper motor component test as outlined in this section.
• Did the windshield wiper motor pass the component test?

Yes
The system is operating correctly at this time. Concern may have been caused by incorrect binding pivot arm adjustment. REFER to Wiper Blade and Pivot Arm Adjustment in this section. TEST the system for normal operation.

No
INSTALL a new windshield wiper motor. REFER to Windshield Wiper Motor in this section.

• Windshield Wipers Continue to Run When Turn Signal and Windshield Wiper Switch Are Turned OFF

• Damaged turn signal and windshield wiper switch .
• Damaged windshield wiper motor .
• Damaged windshield wiper control module.

Pin Number Circuit Circuit Function 1 57 (BK) Wiper Motor Ground (Park) 2 28 (BK/PK) Wiper Module to Wiper Motor (Park Switch) 3 65 (DG) Wiper Motor Power (Park Feed) 4 61 (Y/R) Wiper Motor Common (RUN) 5 56 (DB/O) Wiper Motor LO 6 58 (W) Wiper Motor HI
Windshield Wiper System The windshield wiper system consists of :

• Windshield wiper motor (17508) (F-type).
• Washer system.
• Windshield wiper control module.
• Turn signal and windshield wiper switch (13K359).

The windshield wiper control module is:

• Located at the instrument panel fuse panel.

The windshield wiper motor is:

• Attached to the cowl top extension (021A36) .
• Connected to windshield wiper mounting arm and pivot shaft (17566) .

The turn signal and windshield wiper switch features a:

• Rotary wiper switch.
• Push type washer actuator.

OFF/Low/High Speed

• Has a two-speed, permanent magnet, three brush electric windshield wiper motor .
• The windshield wiper motor has a brush rigging that permits selection of low or high speed.
• When the turn signal and windshield wiper switch is in the LO position, the common brush and the blue/orange wire brush are used, and the windshield wiper motor operates at low speed.
• When the turn signal and windshield wiper switch is in the HI position, the common brush and the white wire brush are used.
• In HI position, electric current will bypass a portion of the armature winding causing the windshield wiper motor to operate faster.
• When the turn signal and windshield wiper switch is moved to the OFF position, the windshield wiper motor will continue at low speed until the park switch outer contacts open.
• When the park switch contacts open, the windshield wiper motor stops in the park position.

Interval
When the turn signal and windshield wiper switch is in the interval position:

• The wipers make single wipes separated by pauses.
• The rotary switch is on the end of turn signal and windshield wiper switch .
• The length of the pause can be set from approximately 1 to 17 seconds.
• Length of pause decreases as the rotary switch is rotated away from off.
• Length of pause increases as the rotary switch is rotated toward off.

While in the interval wiper mode:

• It is normal to hear a slight click at the beginning of each on/pause cycle. NOTE: When using interval wipers, the first wipe may not occur until after a pause of up to 17 seconds.
  

can you here the motor if you can take end caps off an tighten bolts

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.