Plan:
Aftermarket HU w/ Android Auto
Use factory amp w/ factory speakers (they’re not bad, and cuts down on cost)
MAYBE get a small ~35w amp to power the center channel, or other option…
The goods:
Pioneer AVH-4200NEX
Backup camera
Metra double-din adapter (couldn’t find a sosche for a good price)
Metra wiring adapter (w/ green and gray plugs)
Axxess ASWC-1 steering wheel control adapter
eBay HU to factory amp adapter
The stock HU-850 premium audio 6-cd changer head unit only has ON DIN connector, and it’s missing a few leads that other Volvo radios may have. Primarily, it’s missing the illumination and mute leads. only 1, 2, 7-12 exist.
Pinout:
1: +12v constant
2: +12v ignition switched (ASWC red wire here)
|
7: CANbus Hi (ASWC pin 1 pink here)
8: CANbus Low (ASWC pin 7 blue/pink here)
9: +ANT (control/amp turn-on) (HU control and amp adapter red wire here)
10: center channel speaker +
11: center channel speaker –
12: GND (all grounds here)
– Reverse signal will be run from the CEM under the steering column area (I think), pin C:28 (Yellow for 2006 V70R) Edit: running from reverse light at the same time I run the RCA to the rear, much easier for same reason as below.
– Dimmer/Illumination signal will come from CEM pin C:20 (Green) which is the signal for the right side parking light in the headlight (I think… still need to verify) Edit: used the cupholder LED light cable, which is also orange/white. Much easier than accessing the CEM and finding the correct C:20 wire.
– Parking brake signal will be bypassed, since this is only for locking out the video while moving. For my specific Pioneer model, I’ll be using a momentary switch to simulate the on/off/on signal required by the new Pioneer units.
Center panel removal for access to stock HU and CCM on the caR (good time to change out the neowedge bulbs if you’re so inclined).
1. Disconnect the battery (not absolutely required if you’re only changing out the CCM bulbs, but MUCH easier if you unplug the unit so you don’t lose the bulbs during install)
2. Pop out the shifter trim that surrounds the gear selection indicator by opening cupholder cover and pulling up from the rear of the trim.
3. Gear selection indicator is connected to the trim from below. Use a flat prytool or large screwdriver bit to release the tabs on the 4 corners of the indicator module. It should drop down.
4. Once shifter trim is removed, insert key and move shifter to drive, so you have room to access the torx screws and remove the center panel.
5. Locate the two torx screws under the center panel. There are 2 that hold the center console, and 2 that secure the center panel)
6. Once those 2 torx screws are removed, simple pull outward from the bottom of the center panel, then pull the panel downwards to release it from the catch at the top.
7. You’ll likely have to twist it 90deg to get it out. At this point, you should ahve access to the neowedge bulbs behind the CCM if you want to change them out. however, I highly recommend removing the CCM to make install easier.
8. CCM is held by 3 torx screws in the back. Locate and unscrew (helps to have a magnetic screw retainer so you don’t lose the screws, as there is a big gaping hold right under your workspace. Then release the tabs on the side and CCM will slide right out.
9. Silver trim is held on my a few torx screws as well, those need to be removed to access/remove the stock HU.
10. For installing an aftermarket HU, remember to REMOVE MATERIAL FROM THE STOCK HU HOLDER so that your new wires will clear and you’ll have access to ALL the plugs behind the new HU. Otherwise, you’ll be going to town w/ pliers like I did. Not ideal, but works.
Harness is pretty much done.
Since I was fiddling w/ the dash, I installed some blue T4 LEDs to sorta match the cluster. I used a red LED for the defog and seat heater because, well, it makes sense? Color is washed out, the red is REALLY red and the blue is more blue. This should match my head unit once it’s installed. If only I could change the LEDs inside the switched now…
Although I think I need to get a brighter LED for the middle light.
The rest will be done this weekend when I start tearing apart my car. Heck, it’s Friday night and I got nothing better to do 
Out comes the center console for a good cleaning (previous owner spilled some Starbucks and areas normally inaccessible were gunked up with sticky sugar syrup). While center console was out, I decided to install the HDMI/USB port in the empty panel under the rear 12v socket instead of inside the storage area. Mostly because I like storage space, and having a cable plugged into the middle of it would intrude on the usable space.
Had to dremel out a bit of the rear housing part as well so the cables would clear
Routing the wires and zip tied them under the console.
While center console was out, I decided to install a semi-hidden switch for the parking brake defeat on my head unit. (new Pioneer units require an on/off/on signal to disable the lockout) Made the cut slightly too large, but it’s not really noticeable where this is. Also, only had access to a lighted switch (didn’t connect 12v, so no light, switch stays hidden)
Routed the mic to the stock mic position, which is covered by a small cap that comes off by twisting it.
Mic installed angled towards driver.
Mostly wired up now.
It’s ALIVE!
Pic of the parking brake switch. It’s not noticeable at all.
I’ll do the rear view camera later.
As for the rear view camera, I located the CEM, but there’s so many plugs and wires, I con’t find which one was wire C20… so I think I’ll just run a lead with the video cable and tap into the backup light. Easiest way. Now I just need to figure out where to route the cable…
Update 5/14: Took off door card. Those pop-out plastic rivets are confusing. First time seeing those. Broke a few before I realized what was going on. Updated version of the plastic rivets are much better, as the center part stays in place. Ordered a few as replacements from Tasca.
Update 3/14/18: CENTER CHANNEL hookup. I did this when I installed everything, but I’m putting the info here for ease of reference. You can remove the un-used wire leads from the harness if you want to, but it’s not necessary. However, I highly recommend this since there’s not a whole lot of room back there, especially with the additional RCAs and the Axxess box.
To hook up a pseudo center channel, use EITHER front left (-) and front right (+), OR front left (+) and front right (-). Yes, that’s right, one (+) and one (-) from the LEFT and RIGHT. This is called bridging channels. This normally doubles the power output to a speaker. HOWEVER, normal speakers are 4ohm resistance. Since your stock speaker is 8ohms, thus causing a halving in the power, it all works out. =)