[RenGray]

Hi there all I've got a long story and I sure could use some help if anyone has experience in this area.

I'm a mechanic and have been one for about a decade and a half. I have a lot of experience with most makes and models but I'm not super up to speed on BMW. I replaced an engine for a customer in his 2013 BMW 28i with the N20 engine. I diagnosed that he had a timing chain failure in the engine was locked up, that it wouldn't crank and you couldn't turn the engine with a 5-ft breaker bar.

Skip forward and he orders a 2017 N20 for me to put in. We research what components need to stay and what components need to be transferred over in order for the swap to work. After about a week of work I got the old engine out and the new engine in. I've got everything hooked back up the way it should as far as I can tell minus the radiator because we are also replacing that.

We are using the old computer with the new engine so that we wouldn't have to reprogram. I transferred the cam sensors and the high pressure fuel pump from the old engine to the new engine. I transfered all fuel injectors and coils to their respective cylinders they came from. . I was pretty meticulous in marking where every connector went so I am fairly confident I've got all of the connectors for the engine in the right spots.

I'm currently getting a crank no start condition, a drivetrain warning, and an ignition warning. The computer is storing three codes whenever I try to crank it up. Those codes are as follows

121002 - charging pressure sensor short circuit to earth
1f1a91 - dme monitoring 5v sensor supply 2: voltage outside valid range
I do not remember the number for the other code, however it was something to the fact of "engine oil pressure high" I believe it was 1c3101.

I have confirmed that I have air, compression, fuel, and have a spark tester on the way to test spark. However when I tested Spark by shoving a screwdriver into the ignition coil and placing it near a suitable ground, there was no arc on multiple crank attempts.

I've scoured my work to see if I missed a connector, if I missed the ground, I've checked connector pins to make sure they haven't been bent, I've checked connector female ports to make sure they are correctly pinned, the only thing I haven't done is really dive into the fuses because I don't have a solid Source on what fuses are what. I'm also wondering if the little junction box that contains fuses that is under the windshield cowl on the driver side under the hood may have an issue. Integrated supply module I believe it's called?

If anyone may be able to lend a hand to help me figure this out and finish this job for my customer I would tremendously appreciate it. It's going on two weeks now and I'm pulling my dang hair out.

[tom2021]

I hope this posting help. Good luck.

https://x3.xbimmers.com/forums/showthread.php?t=1945596