THE REAR DOOR FOR THE REAR/TRUCK WINDOW WONT GO DOWN. WANT TO KNOW IF IT HAS A FUSE TO CHECK AND WHERE IS THAT FUSE LOCATED?

You say the driver window works? wouldn't be a main fuse or fusible link then -driver door locks and window wouldn't work either. Each door has a module inside (computer) . The driver door has a circuit breaker power feed an a fuse DDM fuse 10amp located in rear junction block circuit breaker is located in under hood maxi fuse block. The circuit breaker also feeds battery voltage to the other door modules too. PDM - passenger door module fuse 10amp located in the instrument panel fuse box and the RDM - rear door module RDM fuse 10amp located in the rear fuse box - under the back seat.

Each power window is connected to a permanent magnet motor. The motor raises or lowers the glass when the door module applies voltage to the motor. The direction the motor turns depends on the polarity of the supply voltage provided by the associated door module. The 2 front doors have their own separate modules. The rear seat contains a single module, which controls both of the rear power windows.
A serial digital communications link, called the simple bus interface, is used for communications between door modules and the driver's door power window switches. The use of serial digital communications allows the use of a single wire to convey switching information between the power door lock switch and the driver's door module (DDM). The serial communication is also used in order to transmit switching information from the DDM to the other 2 door modules.
The door modules apply battery voltage of the correct polarity to the respective window motor when any local, or power door lock switch, UP switch is operated, driving the window up. Battery voltage is applied to the respective window motor in the opposite polarity when any local, or power window switch, DOWN switch is operated, driving the window down.

Driver Door Module (DDM)
The driver's door module (DDM) directly controls the driver's door window motor and the express down window feature. The DDM sends window UP/DOWN messages received from the power door lock switch to the passenger door module (PDM) and to the rear door module (RDM) over the simple bus interface (SBI) line. The DDM also contains a class 2 data link which communicates with the other vehicle system modules. The left front power door locks and the outside power mirror are also controlled through the DDM.
Passenger Door Module (PDM)
The passenger door module (PDM) controls the passenger's door window motor. The PDM controls the passenger's door window directly from the right front power window switch or from instructions over the simple bus interface (SBI). The right front power door locks and the outside power mirror are also controlled through this module.
Rear Door Module (RDM)
The rear door module (RDM) controls both of the rear door window motors. The RDM controls the rear windows directly from the rear door window switches or from instructions over the simple bus interface (SBI).

Without knowing what your dealing with ,and just replacing parts is futile at best . Do you know what all is involved in the power window electrical circuits ?
Power Windows System Components
The following components are used to control the power windows:
• Driver Door Module (DDM)
• Passenger Front Door Module (PDM)
• LH Rear Door Module (LRDM)
• RH Rear Door Module (RRDM)
• Driver Door Switch Assembly (DDSA)
• RH Front Power Window Switch
• LH Rear Power Window Switch
• RH Rear Power Window Switch
• LH Front Power Window Motor
• RH Front Power Window Motor
• LH Rear Power Window Motor
• RH Rear Power Window Motor
• Class 2 serial data circuit
• Power door serial data circuit
• PWR WDO 30 Amp Circuit Breaker
• DRVMDL Fuse (10 amp)
Driver Door Switch Assembly and Driver Door Module logic, Driver Door Module internal driver operation
• PASS MDL Fuse (10 amp)
Front Passenger Door Module logic and internal driver operation
• RRDR MDL Fuse (10 amp)
Left Rear Door Module and Right Rear Door Module logic and internal driver operation
Power Windows Operation
The vehicle is equipped with power windows controlled by the door modules. Each passenger door window can be operated, either from a switch built into the driver door switch assembly (DDSA), or from a switch mounted locally to its associated door. The driver door window can be operated only from the driver door window switch built into the DDSA.
When a window is operated from the DDSA, the DDSA interprets the window switch signal as a specific window switch request and sends the information to the driver door module (DDM) via the power door serial data circuit. The DDM examines the request and checks to see if it has received any class 2 serial data messages from any of the other vehicle modules (i.e. ignition switch position) prohibiting the movement of the window. If the window being operated is the driver door window, and if no prohibitive class 2 messages have been received, the DDM then applies voltage and ground to the driver door window motor to move the window glass as requested. If the window being operated is a passenger door window, and no prohibitive class 2 messages have been received, the DDM sends the request, via the power door serial data circuit, to the appropriate passenger door module. The passenger door module then applies voltage and ground to the passenger door window motor to move the window glass as requested.
When a passenger door window is operated from the power window switch mounted locally to its associated door, the passenger door module first checks to see if the DDM has received any prohibitive class 2 serial data messages. If there are no prohibitive messages, the passenger door module powers the associated passenger door window motor.
Both front door windows have the express down feature. This allows the front door windows to be fully opened by momentarily pulling the appropriate window switch lever to the second detente and then releasing.


Door Modules Power and Ground
In order to control power window operations, as well as other door functions, door modules must be powered up. Battery voltage is supplied from the rear fuse block, through separate circuits, to each door module. Each door module is separately grounded through a ground stake. The door modules also use these voltage and ground supplies to provide power and ground to their associated window and lock switches. The front door modules, in addition, use these voltage and ground supplies for outside rearview mirror operations.
The DDSA battery voltage circuit is fed, through the DDM, by the DRVMDL 10 amp fuse located in the Rear Fuse Block.
The DDM battery voltage circuit is fed by the DRVMDL 10 amp fuse located in the Rear Fuse Block.
The PDM battery voltage circuit is fed by the PASS MDL 10 amp fuse located in the Rear Fuse Block.
The LRDM battery voltage circuit and the RRDM battery voltage circuit are both fed by the RRDR MDL 10 amp fuse located in the Rear Fuse Block.
These circuits are in the C1 harness connector of each door module and must not be confused with the door modules voltage and ground circuits that are used exclusively to drive the power window motors.

Do not know of a "Window Relay" for a 2-door M3 convertible. But there is a "Window motor to regulator" in the door itself.
However, there are two 30 amp fuses (#14 and #19) located in the plastic front power distribution box located in the left-hand rear corner (nearest the driver) of the engine compartment that I would check to see if this is your problem before digging down into door interior disassembly. The numbers are marked look under box cover.

Have you tried the child locks on the doors?

open the door to the drivers side and on the side of the dash is a panel remove it by turning the button ..read inside of the cover for the fuse .if you need to know exactly which one it is i can run down to my truck and check it for an exact location

I have the same problem. Do not know cause but I remove large red 50 fuse in engine compartment fuse box, wait 15 sec and replace. Lock car and unlock. This seams to reset something and car is fine. This problems seams to appear when my battery is low.(?)

If I understand correctly, none of your windows will operate at all. No up or down in the front or the rear. If this is the case, the buzzing sound you here may very well be the relay that controls power supply to the power windows. If you do not have the owners manual which will have the legend for all fuses and relays, see if you can get someone to help you. One person can operate the window buttons while the other traces down the location of the buzzing sound. If ALL windows make the same buzzing sound then you have lost your main ground to the power window circuit.This again would involve the malfunction of that same relay. Happy hunting and good luck, Dana

The first thing to check is if this car has a rear window lock button as a child safety feature. These buttons are usually located somewhere on the driver's door. Sometimes you push them by mistake and then you think your windows aren't working.

The second think to check is the fuse box. Check your owner's manual for the exact location. There should also be a fuse box diagram. It's possible the the rear windows are on a separate fuse and all you'll need to do to is replace it. If it is a fuse make sure your replacement is rated at the same number of amps as the original.

The rear window has to be completely down in order to move the tailgate! You should be happy that your window is stuck up, unlike mine which is stuck all the way down! I have to completly take apart my tailgate!! If you want to try a trick to get the rear window down, my bronco has a rear window switch right next to the headlight knob, take the 2 purple wires on that window switch, and cross them, if your motor still works and if the wires are good, that should make the window go down!!! good luck, hope that helps!

The fuse for the rear window is a 30amp fuse located under the drivers side of the dash. It should be the only 30 amp fuse in that fuse box. Also there is a relay that controls all the functions of the back door. It is located inside the rear door. Let me know if you need any further assistance.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jonathan_3a3c556b4b17d1d2