2007 Chevy Tahoe: rear liftglass won't open, neither from the remote, nor the button above the license plate. Rear Wiper won't work either. Buzzing sound if rear water button is pushed, no sound with rear wiper switch.

Sounds like you might have a bad multifunction switch. You can test the outputs of the switch to confirm.

Liftgate Window
The liftglass can be released placing the transmission in P (park), unlocking all the doors and then pressing the liftgate window release switch located next to the license plate light. The BCM monitors the liftglass release signal circuit and when the switch is pressed, the voltage drops below 1 V. When the BCM detects the voltage drop, it will send a liftglass release command to the rear window wiper motor which will provide voltage to the liftgate window latch assembly and will activate the liftgate window release actuator to release the liftglass

I would take it to a qualified repair shop that has a professional type scanner that can view BCM DTC'S - diagnostic trouble codes an can view rear hatch switch input data
DTC B3265 00: Trunk/Hatch/Liftglass Release Output Circuit

The liftglass release switch is an input to the body control module (BCM). The BCM supplies battery voltage to the signal circuit and when the release switch is activated the signal circuit voltage goes low. The BCM controls the liftglass release actuator through the rear wiper motor control module. When the release switch signal is activated the BCM applies battery voltage to the liftglass latch release signal circuit. The rear wiper motor control module supplies voltage to the release actuator through the liftglass release actuator control circuit.
DTC B396F 06: Liftglass Ajar Output Signal Circuit Short to Ground or Open
DTC B396F 0B: Liftglass Ajar Output Signal Circuit Current Above Threshold

Does your vehicle have a Power Liftgate or manual ?

Call the dealer and order a new part.

[PDF]Wiring Diagram.pdf - Ken Gilbert

ken-gilbert.com/wrx/mans/99.../Wiring%20Diagram.pdf

Each connector number shown in the wiring dia- ... Rear defogger cord (Ground). Fuel tank cord,. Roof cord, ... circuit. Then check the switch, relay, fuse, ground, etc. 4. .....Rear wiper motor. Rear wiper ... License plate light RH. Tail light LH.

#? license plate light - Circuit Wiring Diagrams

circuitswiring.com/tag/license-plate-light/

2008 Volkswagen Newbeetle Main Fuse Box Diagram 2008 Volkswagen Newbeetle ...Parts: rear window defogger, shift lock, battery positive voltage, interior light, A/C clutch, ... brake light, daytime driving light, wiper and washer system, vacan, fuel pump, central ... 1997 Suzuki Geo Tracker Left Dash Fuse Box Diagram.

#? license plate light - Circuit Wiring Diagrams - Page 3

circuitswiring.com/tag/license-plate-light/page/3/

Audi A4 Engine Fuse Box Diagram Audi A4 Engine Fuse Box Map Fuse Panel ... mirror control, wiper, washer, horn, brake light, cruise control, heated rear window, ... 2003Suzuki Aerio Dash Fuse Box Diagram 2003 Suzuki Aerio Dash Fuse Box ... rear defroster, fuel injection controller, radio, A/T controller, hazard light, ...

If the contacts that go to the door lock are corroded the switch will not work. Spray WD-40 from inside the vehicle into the space between truck and the door on the passenger side. A few squirts near the high to middle of the side of door should give enough conductivity to energize the lock.

I have a how to tip for exactly this same problem with 2005 Tahoe. Do a fixya search for FIX 2005 TAHOE REAR WIPER.

I found this URL on internet http://www.chefseattle.com/blog/site-news/suburban-rear-liftgate-wont-unlock-how-to-fix/ It might fix your problem. Also while you have the panel off, consider doing the fix rear wiper how to tip I have posted before it fails.

Once you get the nut off of the shaft use a pair of plyers or channel locks and wiggle the base back and forth it iwll come off and then you can replace the wiper assembly without taking anything else off.

I found this URL on internet http://www.chefseattle.com/blog/site-news/suburban-rear-liftgate-wont-unlock-how-to-fix/ Maybe it will help you.

if they are controled or usually opened electrically, then it is probably a fuse. Check your fuse panel