Just placed an order on pioneer avic-w8400nex. When browsing through product info I realized I'll need to install GPS antenna. What would be best location for it? Ideally somewhere totally invisible. I was even thinking about bringing it somewhere under the front hood but I'm not sure if metal won't disturb the signal. Thanks in advance.

 

The OEM antenna is under the plastic windshield cowl, bottom of the passenger side windshield, near the battery. There's a hole in the firewall with a grommet behind the battery to route the cable inside. That's a decent spot.

I've also mounted the Pioneer GPS antenna on the back of the rear view mirror on many cars, routing the cable along the headliner, down the a-pillar, and directly to the head unit. The antenna itself has a magnetic base. The Pioneer HU includes a metal "plate" with adhesive on one side to attach wherever you want. Trim it with scissors and stick it to the back of the rear view mirror. Mount the microphone on top of the mirror and route the cables together at the same time. Works perfectly.

 

Thank you! I'm receiving unit tomorrow and will have a look at the antenna etc. In the past I had to remove the headliner so I understand exactly your suggestion to run the wires through the pillar.

 

I don't use my center channel, so I removed it and mounted my GPS antenna there. It's also an option if you don't feel like accessing the firewall channel.