1990 760 Turbo no start after checking codes

[Richiebuonanotte]

Hello,
Swapped out my TPS this morning to see if it would fix an idle issue. Car started, problem persisted, all good. I proceed to test the fuel system and ignition from slots 6 and 2 on the OBD I module. Have done this many times. Everything seemed fine. I then go to start my car and now it won’t even crank. Dash lights up like normal. I could hear a relay clicking underneath the radio as I try to start, fuel pump turning on. Checked all fuses…all good. What’s strange is the tachometer is jumping intermittently as I try to start and I could hear the passenger seat switch clicking along with that relay…intermittently. Now the seat switch is also functioning intermittently. Lots of intermittent things happening. Anyway I’m at a loss. Wondering if I burned out my ecu during testing. Any advice would be great.