How to install headunit and steering wheel controls

[lup15]

This is a guide for MPS3 with Bose. It should be very similar for the non-bose cars, but I cannot guarantee it. This guide is if you are changing the headunit only and keeping the rest of the system stock.

This is intended as a guide only and maybe different for your car, please double check everything before continuing. Having said that, it’s highly unlikely it will be any different. I TAKE NO RESPONSIBILITY

As I have a pioneer headunit some parts are specific to this headunit. You can check the part brand's website to see if they have a similar part for your brand of headunit

Some information has been obtained from external sources, and where due, are owned by their respective owners

Read through all of this guide to get an idea what to do and also plan your install


Difficulty: intermediate (basic electrical knowledge required)

Time required: 1-2 weekends (2 if you are removing a lot of the dash)


Parts needed in addition to headunit:

• Steering wheel interface, part # SWI-PS (pac-audio.com). Approx $70 from ebay
• Metra Harness part # 70-7903 (Metra Electronics). Approx $30 from ebay (only if you don't want to hack factory harness)
• Dash surround kit. (japanparts.com) This is a genuine mazda part from Japan hence the price. Approx $250-$300 (you can get cheaper dash kits from ebay)
• RCA audio cable - doesn't need to be long, shorter the better (only required if you have Bose system)
• Electrical wire
• Electrical tape
• bullet terminals (female & male) 2 boxes - I got this from Jaycar which also had heat shrink ends. Otherwise go to Bunnings as the normal bullet terminals from Jaycar SUCK
• Wire taps + corresponding size female blade terminal (from Bunnings)
• solder

Tools:

• heatgun if you get the bullet terminals with heatshrink (or use a candle like I did )
• philips (+) head screwdriver
• pliers
• soldering iron
• crimping tool if you have one - otherwise you will need a utility knife to shave off the cable sheath
• voltmeter (optional)

Misc:

• Blanket or something soft for all the dash pieces you will remove
• beer

Planning:
To minimise the time your car is off the road, its best to think about exactly what you need to do. Best to get as much info specific to your headunit, particularly the wires which need to be installed.

Also if you need additional parts like the steering wheel interface or dash surrounds, buy all required additional parts in advance.

Read all installation instructions for the parts you are going to install

Read through the whole of this guide so you get an idea as to what is involved and how you can tailor it to your install.

Taking apart the dash:
You don't have to take apart all of the dash as it depends on what you need to install. For me as I have a navigation headunit with bluetooth and Ipod, I pretty much needed to take apart the whole dash to route the cables. Just follow the instructions of the areas you need access to.

Remove headunit
Follow these instructions: Remove Madza 3 Headunit

Remove centre console
Follow instructions until p3 in below attachment for installing shifter bushes
Shifter_Bushing_Install_3.pdf

Remove glovebox
When the headunit was removed, you would've taken the long plastic dash strip off. Afterwards:

• Remove 2 screws holding the glove box at the top.
• Remove passenger scuff plate
• Remove passenger kick panel (there is a plastic press lock tab)
• Pull glovebox towards you. The glove box is held in by clips.

Remove aircon controls (requires removal of glovebox and centre console)
This bit is annoying as its very difficult to remove the panel even after the screws are removed. You need to take the face panel off to remove it, but its very difficult with the controls still in the dash.

• Remove the screw on the bottom right where the glove box was as shown in this picture.
  dash4.jpg
• Pull the plastic trim off the support next to where the screw was
• You can now move the dash where the aircon controls is still hooked in, which will allow you to wriggle the controls out
• Unclip wiring

Remove centre dash (centre aircon vents)
When the headunit was removed, you would've taken the long plastic dash strip off. Afterwards:

• Unscrew 2 screws holding the cover down
• the part is held in by clips - carefully remove
• unclip wiring

Remove drivers lower dash

• Unclip bonnet latch
• Unscrew 2 screws
• Remove drivers scuff plate
• Remove drivers kick panel (there is a plastic lock tab)
• Part is held in by clips

Remove cluster and steering wheel surrounds (requires removal of drivers lower dash)

• Unscrew 3 screws located underneath of steering wheel surround
• Remove surround (will take some wriggling with the steering wheel lock)
• Top half of steering wheel surround is joined to the cluster surround. This part is all held in with clips
• Cluster is held in by 3 screws (1 top, 2 bottom)

Installation
Disconnect the battery!

Getting line level output to connect to factory harness
Before you start installing, if you have Bose, you will need to fab up RCA cables to connect to the wiring harness. This is so you don't double amp the sound, which is what will happen if you use speaker level outputs from the headunit.

1. Get some audio RCA cables and cut it in half. You only need the terminals and probably 1-2inches of cable.
2. Strip the shielding off so that you expose the wires. Inner wire is +ve and outter -ve
3. Twist the wire then crimp the male bullet terminal onto each of the -ve and +ve as shown in below pic
4. Do this 4 times as you need 2 sets, for front and rear speakers, left and right

rca.jpg

Headunit wiring
How you wire the headunit harness to the factory harness is up to you. However if you plan to change the headunit later down the track back to stock, it would be best to get the Metra harness. I have chosen to get the Metra harness, which is what the below instructions will be for.

Check that the wire colours and their locations are the same on the factory harness as the wiring diagram attachment. If not, then you will need to use a voltmeter to see what your wires are.
wiring_diagram.txt

1. Wire up the headunit harness to the Metra harness using the below attached wiring diagram EXCEPT the Illumination and speaker wires. You can either hardwire directy to the Metra harness, or like I did, use bullet terminals
   
   Note: The Metra harness had the remote wire (Blue) in the incorrect pin. Not sure if they are all like this, but if it doesn't match up with the Factory harness, move the pin.
   
2. Wire the Illumination wire of the Metra harness to the ashtray light. Even though the factory harness provides illumination, it does not provide a good signal and caused my headunit not to dim unless I dimmed the dash less than maximum brightness
3. Connect the RCA to your headunit and then connect to the corresponding speaker location (eg. FL or FR) to the correct -ve and +ve wires on the Metra harness

If you just have a standard headunit without any extras, you're done with the wiring.

Navigation specific wiring
If you have a navigation headunit, you will need some additional wiring done. I didn't do the parking brake or reverse as I didn't need/want to. However, I wasn't able to find a Vehicle speed sensor signal. If anyone knows where to find it, would be great. I have attached what info I did find, but it did not work.

• Parking brake wire is easily found at the parking brake
• Reverse signal can be tapped from the rear
• Vehicle speed sensor?

Cable routing and management
It's extremely tight behind the headunit and there's little room directly behind the headunit. I cut away the plastic part directly behind the headunit to give extra room as shown in below pic. You will most likely will need to manage the routing of the wiring and also misc cables. Theres a decent amount of room below the headunit, behind the aircon controls. Hence its easier if you remove the aircon controls.

The following is what I have done in regards to routing the cables. Looks messy, but you're not going to see it anyway.

• I put my Ipod connection cable in the glovebox. Theres a part which pops out at the back of the glove box. Cut a hole and stick a grommet to make it look neat.
• The GPS antenna was placed under the centre aircon vent. The signal I get is not effected in anyway.
• Bluetooth mic was fed through between the cluster trim

dash0.jpg

Steering wheel controls
Follow the instructions that PAC provide. They are good enough :P. You do have to ground the wires that they say to ground. I just used a wire joiner to tap into the Metra harness ground

The response of the controls is like factory. Some people mentioned lag or needing to press the buttons harder. Same as before for me.

[lup15]

And pictures of final install. The info panel still displays the aircon info and AMB temp. It's not showing in below pics as I didn't have it in the ON pos.

[luke 3mps]

WOW u took apart ur whole dash. when i put my touch screen in, i took the trim off that runs just above the glove box to the drivers dash. this allows you to get to the 2 screws for the head unit, the bottom part just clips out. i had a metra dash kit mounting for the head unit and trim + wire harness. i connected the wires to the metra harness and jvc touch screen harness in the lounge room one night. had the stock unit out and new unit in 2hrs.( i ran it with boston accoustics amps and pro fronts+rear coax's) amp rack i weilded up painted sub box made and tuned, wires to suit took me 3 days to do it all.. had my dad help me extra pair of hands when i needed

Good write up tho

---------- Post added at 10:07 PM ---------- Previous post was at 10:05 PM ----------

that was in my neo tho...

[lup15]

yea had take apart the dash as I've got navi/bluetooth/ipod

[luke 3mps]

do u still get the climate control stuff to work?

---------- Post added at 10:13 PM ---------- Previous post was at 10:10 PM ----------

i mean does it still appear in ur screen above ur head unit, as it did before?

[lup15]

yea, the info panel works fine for the aircon stuff and AMB temp. Obviously it doesn't display the time or the centre bit as that was associated with the factory headunit

[buzurk]

Im confused as to why you dont need the BOSE cable?

my mate put one in his MPS a pioneer double din and he was told he needed a BOSE cable to connect it up
but your saying we dont?

[Ranton]

Whats the unit you installed?

[lup15]

Im confused as to why you dont need the BOSE cable?

my mate put one in his MPS a pioneer double din and he was told he needed a BOSE cable to connect it up
but your saying we dont?

bose cable? I think that's if you hook the bose amp directly to the headunit speaker outputs, i.e. off the harness. What I did was get line level outputs from the RCA preouts of the headunits. its better this way anyway, as the signal is not processed.

Whats the unit you installed?

Pioneer F20BT

[buzurk]

Ok, just to clarify

your using the Front and Rear RCA outputs of the deck to feed the stock AMP, eliminating the need for a BOSE adapter?

THats a much better idea. and the osund is till loud?