First threw code P2017, 'fixed it' but now it shows no code no crank no start

What is your question?

First it threw code p2017 after spark plug replacement. Went to start initially and heard a bang in what sounded like my 5th plug port, took everything apart. Found 2 harnesses plugged but not clicked closed, and inspected all my plugs again, no liquid in plug housing port or burn. I had discovered that 2 of the wires coming out of the back of one harness when reinstalling the intake manifold and attempted to reconnect them, before attempting to start the car the first time. Then when first start was attempted, code p2017 was thrown and the dash read both Engine and Battery Lights and was showing Trac Off. The car hadstarted to begin its turn over when it died. Based on what all I could tell, I believe it to be intake runner harness, so I also had checked and secured the wires when I went to inspect the spark plug 'bang'. They were all still connected which I found odd. I reconnected everything and double checked everything, and attempted to start again - nothing. No crank at all

What makes this problem better or worse?

Me

How long has your 2015 Lexus IS250 had this problem?

2 days