Tach and temp gauge

[zaphod]

Hello 

My 324d got an m42 transplant from an e36 and the temp and tach gauges are not working.
Now for the temp, I have some ideas about how to get it wired up, but does anyone know how to wire up the tach?
Thanks!

[bmwman91]

The Motronic has an output line that drives the tach. I am not sure how the 324d did it, but I'd assume that the ECU was also providing the signal. You will need to get an M42 coding plug for the instrument cluster though, since the one in there will likely report the wrong RPM since it was for a 6 cylinder.

The temp gauge probably uses the same temperature sender, so as long as that is plugged in and not damaged, you should be OK.

Both of the above signals pass through C101, and it could be that the 324d has them in different positions than the 318iS. You definitely cannot pop the terminals out without the right tool, but thankfully they are relatively cheap. First, find the wiring diagrams for the 324d and compare them to the 318iS.

The relevant 318iS diagrams are on pages 1360-2 and 6210-1.
https://www.armchair.mb.ca/~dave/BMW/e30/e30_92.pdf

[zaphod]

Thanks for the info!
I also managed to find some schematics for the x20 connector, so I will take a deeper look and try to figure it out