After M42 Swap Windows and Tach and radio isnt working!!

[BoricuaBond000]

Hey Fellas,
   I have a 89 325ic and I just completed a M42 swap and now my windows and tach and radio isnt working. I did not touch the wiring at all, the harness wasnt touched either only to be connected in the engine bay. I dont see any
switch above the radio (from references i read online) the switches are brand new, can someone please throw any other ideas, might be dumb but where is the circuit breaker located at? Any and all help would be gladly appreciated.

[DesktopDave]

That's an odd one.  I don't know if the 'vert has a positive distribution block off the battery.  We with hardtops have a distribution block there and once I'd forgotten to hook wires back up after a swap.

The affected circuits are:
fuse 10 for instruments
fuse 12 for radio, check control and instruments
fuse 17 for power windows

There are no circuit breakers that I'm aware of on the 325.  I had a 5-series with them though...

[nickmpower]

there is wiring for the starter that might be different. I forget what it is called but its supposed to cut power to some things when cranking

[BoricuaBond000]

Ok so the window issue is fixed due to a wiring not being grounded, also the radio started to work at the same time, as odd as that is. Now the only other to fix would be the Tach, none of my lights work in my dash to view my gauges, I check the fuses also and they were all replaced, so I'm running out of ideas....

[DesktopDave]

IIRC, the large round C101 connector in the engine bay next to the brake booster is missing the tach signal wire on some models.  The M42 C101 has more pins installed than the older M20 setup.  Twist it apart and look for the same number of contacts in the connector halves.  IIRC the tach runs off a black/blue wire in a 3-pin white connector called C104 above the glove compartment.  Found a few links while researching my M20 eta/auto to i/manual swap:
http://www.akgmotorsport.com/e30convpins.html

This link sounds like your problem too:
http://www.newenge30.com/phpBB3/viewtopic.php?t=253

So I'd test those SI cluster batteries.  Replacements are cheap, a pair is about $20.  I did it myself last year.  Might also just be that the three large cluster bulbs are burned out...it's hard to note when one is out, those larger wedge base bulbs are cheap & available at local auto parts stores.  The little ones are dealer-only, or EBay.