hi
I tring to replace wire harness. I bought 21 circut universal harness. Does anyone used this harness?
I have few issues
1. Fan doesn't work. There is no power on fan cable.
2 how to connect msd 6btm?

 

Whos harness did you use?
AS for the MSD, Wire it as per MSD wiring installation information... Should work just fine.

 

I have 21 circut universal wire harness from China.

There is few methods how to connect msd on msd webside. I tried to do similar how it was connected previously. Thick cables red and black to battery. And small red to coil wire. There is other method to connect tacho cable to white msd cable. Both methods don't work. I have power on resistor. How to check power on coil wire?

 

Are you running the boost controller with it? Or just the 6BTM box by its self?

Note:::: You said (And small red to coil wire.)... That should go to the Ignition 12 switch....
Tach should come off the back side of the box...
Unless I'm reading the wrong stuff??
Im looking at the wiring for the 6462 MSD 6-BTM

https://documents.holley.com/6462.pdf
Look at page 10 and 11
Keep us posted..