I just finished installing my F900bt and have only connected the rear speakers as I don't have anything running in the front.

I have tested bluetooth and navigation audio on this unit before and it has worked fine however I have come to the conclusion that the audio is not being routed to the rear due to how it's been set from factory.

Rather than completely taking apart my dash again and rewiring everything up, is there a way I can route the nav and bluetooth audio to the rear speakers?

Any help on this would be much appreciated.

no... hardware only points nav and blutooth audio to front spearks, youd have to splice the rear spearks in to front inputs in the harness. so that avic thinks its outputting to front but is really running to back. or if yo have spearkers amped switch which RC ports they are plugged into

Or just connect the front speakers.

Yeah, don't have front speakers to connect to unfortunately.

Can I leave the rear speakers connected to the rear inputs and splice them into the front aswell. So essentially have them connected to both inputs? Or will that cause issues.

Regards,

too many variables to answer this, the main one being the wattage on the rear speakers... Pluss I think it could cause other issues with front back issues.