Power door locks on a 2004 chevy tahoe don't work

Check the door ajar switch which is located on the pillar post.

Look at the end of the dash and between the drivers side door for a second fuse panel. I think everything you mention works on one data bus. You can remove the button pad on the drivers door. Since it gets used all th3 time i# might have gone bad messing up the works.

Power windows and the door locks don't work ? How do you know there is no power , did you use a voltmeter an test for battery voltage at the driver door switch connectors ?

Try the Driver Door Module fuse 15A

Have you checked any fuses? You have some bad wires and possibly loose connections in your harness.

If the drivers side does absolutely nothing, there is a chance that power plug that goes into the door has come apart. There is a rubber boot that goes from the cab to the door, that is where the wires run. The power plug is usually right before the boot or right after.

Doesn't lock or unlock ? These relay's are controlled by the BCM - body control module .
I have factory service repair information , 32 steps ! Too much info to post here .

Power Door Locks Inoperative (Rear Door(s))
2
Activate the door lock switches to the lock and unlock positions.
Do both rear passenger doors lock and unlock?
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3
3
Is there only one door lock actuator that is inoperative?
YES - Go to Step 6
NO - Go to Step 4
4
Are the rear door lock actuators inoperative for both lock and unlock?
YES - Go to Step 8
NO - Go to Step 5
5
Do the rear door lock actuators lock?
YES - Go to Step 15
No - Go to Step 10
6
Disconnect the inoperative door lock actuator.
With a test lamp connected to a good ground, probe the door lock actuator lock circuit at the door lock actuator harness connector.
Activate a door lock switch to lock position.
Does the test lamp illuminate?
YES - Go to Step 7
NO - Go to Step 25

Some of these steps can be bypassed because you say they worked after replacing the relay .LOCK RELAY ? right .

7
With a test lamp connected to a good ground, probe the door lock actuator unlock circuit at the door lock actuator harness connector.
Activate a door lock switch to unlock position.
Does the test lamp illuminate?
YES - Go to Step 24
NO - Go to Step 26
8
Remove the rear door unlock relay.
Connect a test lamp to battery positive voltage.
Probe the door actuator unlock control circuit cavity in the left IP fuse block.
Does the test lamp illuminate?
YES - Go to Step 21
NO - Go to Step 9
9
Install the rear door unlock relay.
Remove the rear door lock relay.
Connect a test lamp to battery positive voltage.
Probe the door lock actuator lock control circuit cavity in the fuse block.
Does the test lamp illuminate?
YES - Go to Step 20
NO - Go to Step 22
10
Remove the rear door lock relay.
Connect a test lamp to a good ground.
Probe the battery positive voltage circuit (high current) cavity in the fuse block.
Does the test lamp illuminate?
YES - Go to Step 11
NO - Go to Step 22

If your not familiar with GM diagnostic flow chart's , they can be confusing .
Let me know if you need more diagnostic steps .

2003 chevy tahoe , none of the switches on the driver door works, mirros, door, locks.

check the clamp sensor front and back door

you will have to write your vehicles vin number down wich is if you look throught the windshild on the drivers side you will see it its a little plate with numbers but right down the vin number and take you drivers license and Registration with you to the chevy dealer ship and request the remote for that vehicle. and they should be able to get you one. as far as i know the remote is the only way to get the alarm off. I hope this helps you