A lot of electrical problems

[Mr-Jack]

I just bought a 2004 4x4 Tahoe from a friend of ours. It drives and runs great. regular maintenance on it and all that...but it has some electrical gremlins that I'm looking to eliminate.

First is when you open the driver's door after you turn it off and remove key, the guage cluster lights and radio will stay on until the 7-10 minute time is up. Like it still thinks the key is in the ignition or that the door is still closed. At first I could just open the left rear door and it would shut it off, but now that's not the case. (Was thinking the door latch actuator and sensors, but now kind of leaning towards that and possibly the ignition switch)?

Also, once in gear, it generally locks the doors, and unlocks when I go to park. sometimes it will wait to lock the doors in gear until I've been driving for 10 minutes. and sometimes when I put it in park it doesn't unlock?

Some of the cluster lights don't illuminate like cruise/left blinker...etc temp control backlights aren't working (probably a new panel with that one). Sometimes in order to get the window switches on the driver's door to work I have to smack the door then they'll work. I ordered a new blower motor resistor because I only have 4 & 5 fan speeds.

Do y'all think any of this crap is related...it just seems like a lot of little crap and throwing brand new parts at it might not fix this.

Thanks in advance fellas...

Jack