[fseriesross]

Thank you so much for any replies. Frustrated and bottlenecked by my lack of knowledge. New bmw guy.

I have a 2017 BMW 330i xDrive (b46/48) Msport package if relevant. No modifications thus far. 90k miles. This is a long post I want to be thorough.

The thermostat gave out on my 330i, today the part came in and I began removing everything that was in my way. Due to my impatience with poorly made YouTube videos and lack of info online, I thought it was located on the back of the engine. Anyways from the very beginning battery was unhooked, I took out airbox and related piping, charge pipe, most of the coolant hoses, coolant reservoir, and throttle body. This is where I messed up. I took out the ECU (ECM, IVM, power distribution are some things I’ve seen it called on these forums), I disconnected everything and took out the rectangular aluminum box and plastic box, and upon locating the “heat management module”, I put everything back in. It was all meticulously labeled and went back in the same way it came out. However when I had the entire engine bay back together, heat management module installed, I went to reconnect the battery and start the car, and I get drivetrain malfunction and ABS warnings (didn’t touch anything brake related) on my idrive system. The car not only won’t start, it won’t even crank at all. The starter doesn’t seem to be getting power. Fuel pump is priming but no crank. I took all the connectors back out, blew them out, ensured they were in the right places, and made sure they were seated well, same problem, no crank. I’ve tried everything I can think of. I’m going to link another f30 bimmerpost forum that was solved but the solve didn’t work for me. The only thing OP did in that post that I haven’t tried was clear codes with a reader, I just disconnected the battery for a while in between tries.
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This is my daily driver I’m having to borrow a car any help is greatly appreciated. I will attach some images as well.