Hello, I just picked up a 2004 G35 coupe automatic as a little project. I noticed when I use my key fob to lock the doors, only the driver side locks. The buttons inside the car don't work at all, no clicking or anything. My question is, would it be the master control on either door panel (the piece that has the buttons on it), the window motors and door actuators, a fuse?, bad wiring, or something else? I haven't taken the door panels off in order to save time jsut in case I don't need to and have had trouble determining if there's even a fuse or relay for the windows and doors. The sunroof works fine. Anyone experience this before? If so, how did you fix it? I live in Texas and the heat wave is quickly approaching. I'd like to be able to drop my windows since I also have to replace the A/C condenser. TIA

-LL

 

Probably broken wires in the flexible door loom but you need to troubleshoot everything to be certain.

You can roll the windows up/down by holding the key in the door locked/unlocked position. You can also roll the windows down by holding the unlock button on the fob. See if you can verify the windows are functional at all to isolate where the problem is.

Windows motors / lock cylinder, you can troubleshoot with a digital multimeter on the harness. If you have voltage (reverses polarity for the opposite lock/unlock function) then it's the lock/window motor that failed. If you don't have voltage it could be broken wires, bad master switch (driver door switch) or a bad BCM.

If you can get it to work from the driver door lock that rules out BCM and wiring.

 

key fob doesn't roll windows down. I'm thinking it's either loose/dirty connections in the main switch or the switch is bad. And... I'm pretty sure passenger door actuator is bad since that seems to be a very common problem on this car. If the main switch was bad, would that stop the passenger switch from working as well? Or are the two not related?

 

The passenger side switch sends it's signal to the driver side switch that sends it's signal to the BCM. Everything is controlled through the BCM, all the door locks, window function, lights, everything. BCM sends the output signals to the actual motors/actuators/relays.

Section BL - Body / Locks
Section GW - Glass/Windows
Section PG - Power/Grounding

https://www.nicoclub.com/infiniti-service-manuals

 

Thus you can bypass the window switch by using the fob or the driver lock cylinder to roll down windows. I would start by verifying that you do/do not have voltage at the window motors. Then I would ring out all the wires between the BCM and the lock actuator/window switch/etc. Wiring diagrams are all in the FSM I linked.

 

What is the BCM?

 

BCM = Body Control Module
ECM = Engine Control Module
The master window and lock controller in the driver's door also has some "processing" in it so that's another of the car's many black boxes.

 

Body Control Module, there are quite a few computers on these cars.

Engine Control Module ECM - Controls engine function, located in the cabin below the glove box side kick panel.

Transmission Control Module TCM - Controls transmission function, 2003-2004.5 located next to the ECM, 2004.5+ located inside the transmission.

Body Control Module BCM - Controls windows, lights, locks, etc. Located behind the left side kick panel near the cabin fuse box Fuse Block - J/B

SRS Diagnostic Control Module - Controls airbags, seat-belt pretensioners, etc. Located blow the center console.

VDC/ABS/TCS Control Unit - Controls antilock brakes, traction control, and other vehicle dynamic control stuff.

RAS/HICAS Control Unit - Only on coupes equipped with rear active steering, located in the trunk near the spare tire.

Intelligent Power Distribution Module IPDM - Engine bay fuse box, controls various vehicle systems, everything from the fuel pump, starting, horn, headlights, all connected to the CAN network.

AC Auto Amp - Controls air conditioning functions, also some instrument cluster stuff. Located behind the compass/clock.

 

This car has more separate computer/CAN system boxes scattered across the chassis than anything I've ever seen in my life

 

Thanks for the input guys, I'll be doing my best to diagnose the problem. I hope the windows are because of the master switch panel on the driver door, those are pretty cheap to replace. I'm leaning towards the actuators for the door locks being bad with the more research I do.