My 2005 Impala's electric window and outside mirror adjustment switches have stopped working. I was told by a friend that just replacing the switches won't repair the problem, but he couldn&#

Hi Michelle , what make model an year vehicle ? On some vehicles this is function is controlled by a door module .

In order to control outside rearview mirror operations, as well as other door functions, the front door modules must be powered up. For this purpose, battery voltage is supplied from the rear fuse block, through separate circuits, to each front door module. Each front door module is separately grounded through a ground stake. The front door modules also use these power and ground supplies to drive the mirror motors, and to provide power and ground to window and lock switches and door lock actuators. In addition, the driver door module (DDM) uses these power and ground supplies to power the driver door switch assembly (DDSA) and integral mirror control switches.
Could have DTC'S - diagnostic trouble codes stored in BCM - body control module .
DTC B1544 01: Mirror Motors Common Circuit Short to Voltage
DTC B1544 02: Mirror Motors Common Circuit Short to Ground
DTC B1544 04: Mirror Motors Common Circuit Open Circuit
DTC B1600 01: Mirror Motor 1 (vertical) Circuit Short to Voltage
DTC B1600 02: Mirror Motor 1 (vertical) Circuit Short to Ground
DTC B1600 04: Mirror Motor 1 (vertical) Circuit Open Circuit
DTC B1605 01: Mirror Motor 2 (horizontal) Circuit Short to Voltage
DTC B1605 02: Mirror Motor 2 (horizontal) Circuit Short to Ground
DTC B1605 04: Mirror Motor 2 (horizontal) Circuit Open Circuit .

probably needs a new switch.

Had a similar problem with my 2008 Volvo S40 and traced the problem to the window switch circuit board. I replaced this and problem was solved.

Could have a DDS an PDS .depends on what RPO code yours has >
Outside Mirror Description and Operation (with RPO DL3)
Or
Outside Mirror Description and Operation (without RPO DL3)
Without
Heated Outside Rearview Mirror Operation
The REAR DEFOG relay controls the operation of the heated outside rearview mirrors. When rear window defogging is requested, the REAR DEFOG relay is energized and B+ is applied to the supply voltage circuit of the mirror heater element, located in the mirror face. A constant ground is also applied to the mirror face. Current will pass through the mirror heater element, warming the mirror, so long as the rear window defogger is commanded ON.

With
Heated Outside Rearview Mirror
The DDS and PDS control the activation of the mirror heaters. Upon receiving a serial data message indicating a request for heated mirrors, the DDS and PDS, will apply voltage to the mirror heater element supply voltage circuit. The mirror heaters will remain active until a new message is received indicating rear defogger is to be deactivated.
The power mirror system consists of the following components:
• Driver Door Switch (DDS)--An electronic control module with integrated switches and requires programming when replaced
• Passenger Door Switch (PDS)--An electronic control module with integrated switches, requires programming when replaced
• Power Mirror Direction Switch--Integrated into DDS and is a four position momentary switch that provides a signal input to the DDS for up, down, left/extend and right/retract with a mirror switch activation
• Mirror Select Switch--Integrated into DDS and is a three position switch that allows the operator to select the left or right mirror and also a neutral/fold position
• Mirror Extend/Retract Switch--Integrated into DDS and is a two position switch that allows the operator to select the mirror extend or mirror retract position
• Left Outside Power Mirror--Contains both the vertical and horizontal mirror motors
• Right Outside Power Mirror--Contains both the vertical and horizontal mirror motors
• Body Control Module--An electronic control module that requires programming when replaced, serves as the power mode master and is the main message handler
• Horizontal and Vertical Position Sensors, if equipped with memory mirrors--Supplied a 5-volt and low reference by the DDS/PDS and provide a variable voltage signal to the DDS/PDS that is proportional to mirror position
• Folding Mirror Motor, in each of the outside mirrors, if equipped with power fold mirrors--Provides extend and retract movements of the mirror and is serviced as a complete mirror assembly
Your best bet mite be to take to a qualified repair shop , i really don't think you'll be able to do anything with it.
Do you have wiring diagrams so you know which wires to test ,do you know how to do electrical testing ?
The Driver Door Switch (DDS) and Passenger Door Switch (PDS) supply voltage to the outside rearview mirror heater elements upon receipt of a serial data message from the HVAC module indicating that the rear defrost system is active. The door switch supplies B+ through the driver/passenger mirror heating element supply voltage circuit when a request is seen. Ground is applied through the driver/passenger mirror heating low reference circuit.

I would safely assume your right mirror may be inoperable period then by your statement you are leaving the switch for the mirrors in the middle during switching correct and during adjustment are switching to R/L mirror on the switch? Mirrors are on the same circuit so both should be operable. Have the mirror checked for operation before heading any further. I Think you will find during this its unplugged from its source of power or inoperable period and needs replaced. Remember to rate my solution and leave testimonial PS please purchase you a Owners Manual for your car you will thank me later.

According to BWD and AC Delco the switch is supposed to fit 2000 - 2005 model cars.
Is it possible one has cruise and the other does not ?

Power windows an locks work ok ? Do you know anything about automotive electeronic control modules ?
Power Mirror System
Power Mirror System Components
The power mirror system consists of the following components:
• Driver Door Switch (DDS)--An electronic control module with integrated switches and requires programming when replaced
• Passenger Door Switch (PDS)--An electronic control module with integrated switches, requires programming when replaced
• Power Mirror Direction Switch--Integrated into DDS and is a 4 position momentary switch that provides a signal input to the DDS for up, down, left/extend and right/retract with a mirror switch activation
• Mirror Select Switch--Integrated into DDS and is a 3 position switch that allows the operator to select the left or right mirror and also a neutral/fold position
• Left Outside Power Mirror--Contains both the vertical and horizontal mirror motors
• Right Outside Power Mirror--Contains both the vertical and horizontal mirror motors
• Body Control Module--An electronic control module that requires programming when replaced, serves as the power mode master and is the main message handler
• Memory Switch, if equipped with memory mirrors--Supplied power by the DDS and provides a voltage signal to the DDS upon a switch activation
• Horizontal and Vertical Position Sensors, if equipped with memory mirrors--Supplied a 5-volt and low reference by the DDS/PDS and provide a variable voltage signal to the DDS/PDS that is proportional to mirror position
• Powertrain Control Module (PCM), if equipped with memory mirrors--An electronic control module that requires programming when replaced and provides the message indicating transmission gear selection
• Driver Information Center (DIC), if equipped with memory mirrors--Part of the instrument cluster which is a an electronic control module that requires programming when replaced and is used to personalize the memory recall functions
• Fold Motor, in each of the outside mirrors, if equipped with power fold mirrors--Provides extend and retract movements of the mirror and is serviced as a complete mirror assembly
Each of the outside power mirrors contains 2 reversible motors to provide horizontal and vertical movement of the mirror glass. The vertical motor operates the up and down directions and the horizontal motor operates the left and right directions. If equipped with power folding mirrors, each outside power mirror will contain a reversible fold motor to operate the extend and retract functions. Each of the mirror motors are circuit breaker protected.

Do you know what DTC'S - diagnostic trouble codes are ?
DTC B1023
Circuit/System Description
The driver door switch (DDS) and front passenger door switch (PDS) each contain switches that control power door lock and window functions. The DDS also contains the control switch for the power outside rear view mirrors. These switches are integrated within the door control modules and are not serviceable as separate components. The DDS and PDS monitor these switch inputs for internal faults and set B1023 00 if any are detected.

You could have any number of problems an without testing , hooking up a scanner that can check DTC'S in the door module ,electrical circuit testing etc... we'd only be guessing . Your best bet mite be to take it to a qualified repair shop.

If neither switch works it is a bad connection at the motor or bad ground or a bad motor. Remove the door panel unplug the motor push the switch and see if there is 12volts on the wires if there is the motor is bad There are small brushes in the motor that go bad tap on the motor while pushing the switch if it works that way replace it

the window switch just pops out of door panel.

I had a similar problem with the electric mirror switch. I removed the two screws in the door hand hole and remove the plastic part containing the switches for the windows, mirrors, and door locks. Turn the piece over and remove the connecting electrical plugs. Find the electric windows part and remove the four brass screws. Next use a small screwdriver to remove the switch. Look for small screws in the switch and remove them remove the bottom of the switch and see if the contacts are clean (these can be cleaned with alcohol) then replace everything in the reverse order. This worked for me with the electric mirrors switch. Cost nothing except time.