Why does the FMS not come on until after start

[sharpless281]

Is the FMS on the FMC suppose to come on when the battery is powered on, I am putting the check list in fore flight. I thought the flight plans were usually entered before start. Just asking

[norcali.pilot]

The FMC turns on with the Avionics Master ON with power coming from an external source, battery master, or generators

[sharpless281]

That does not happen. Battery Bus is norm, Master battery on, Avionics On.
It comes on only after engine start and a generator reset/on

Which is exactly what one of the YouTube videos on the product page does.

[kevin_firth]

That does not happen. Battery Bus is norm, Master battery on, Avionics On.
It comes on only after engine start and a generator reset/on

Which is exactly what one of the YouTube videos on the product page does.

2 words, bus ties...?

[sharpless281]

Thank Kevin. I tried to set the MVAMS to ready to start and when I turned on Avionics I still do not see the FMC power up. I am ok with that, just wondered why. It starts after I start the engine and reset the GEN (L or R) so that's ok. I found a few websites on the bus ties so I will do some reading, thanks

[kevin_firth]

Thank Kevin. I tried to set the MVAMS to ready to start and when I turned on Avionics I still do not see the FMC power up. I am ok with that, just wondered why. It starts after I start the engine and reset the GEN (L or R) so that's ok. I found a few websites on the bus ties so I will do some reading, thanks

I'll have a play around tonight to be sure, but I never try to power up the master avionics unless an engine is running or a GPU is connected. In both circumstances I get a powered up FMC. I think I read somewhere that connecting ground power automatically ties the buses? (As I recall)

[kevin_firth]

https://youtu.be/_ZEHTTJ0auc

It was the Gen Ties you were after

[sharpless281]

ok thank u I will try that, it is part of the checklist

Just did that worked with the Gen Ties