Parasitic drain?

[Trkr-ma]

So my 2017 Tahoe, ( I'd like to add, very, very well maintained) has been randomly starting, is how it started out, then nothing. I had a new starter put in it, without running any kind of diagnostics. Worked one day, then nothing. As I researched on YouTube, I have become familiar with parasitic drains. Due to bad relays. I also saw loose fuses, bad fuses, etc. I haven't gone through all my relays yet. It would not start with one of them jumper boxes. So I dug the big guns out and charged it today, with 400 amp charger. It started right up. I might add a couple weeks ago, I jumped it with another vehicle, it started, but it was drained overnight. Then, no start with jump. Any thoughts on specific relays that I would need to check? I have been online, I have a list of relays to check from YouTube. I just got so frustrated I stopped.

 

[Fless]

Is this a "no crank" or a "crank no-start?"

 

[Fless]

For a parasitic drain you can measure the voltage drop across the fuse test points, and use the chart to convert to mA. Here's the chart for Mini Fuses: https://m.roadkillcustoms.com/wp-content/technical-pdf/Mini Fuse Voltage Drop Chart.pdf Any fuse that has a voltage drop is carrying current. Isolate the circuit, then diagnose it.

Here's a video on testing: