Firstly the base stereo that BMW install is mediocre to put it subtly.
I have upgraded the front door speakers to Logic 7 speakers and added L7 tweeters/Logic 7 under seat subwoofers
Please see link on how to change door speakers (thanks goes to the creator of this video)
Now moving onto amp installation, would like to thank B33mers excellent how to guide, help and advice from following makkan00, Parapaul, Rudz, Ram335i, Technic, Rudz, AWBimmer, MEGA, mob17, my cousin Danny who came to help me out– (I may have forgotten some more names I do apologise)
Disclaimer – I cannot be held responsible if anything goes wrong as I have written this as guide to help understand if you are thinking about upgrading. If in doubt seek professional advice.
Tools – need basic toolkit with various torx bits/soldering iron/screwdrivers/plastic trim removal kit (I did not have one of these but used the plastic end of a paintbrush (you will see it many times used)
The HU has been recoded to HiFI
The amp I used was a JL audio XD400.4 amp/Technics harness/Amplifier wiring kit
• Remove the long trim that runs across the dash, you will need to insert a plastic trim removal underneath and prise out gently. May need another screwdriver to help move along (I masked mine up to prevent scratches). The trim is held on by 2 long metal pins either end (and 2 in the middle) and once you prised it out you can pull off with your hands gently
• You will need to disconnect the starter button wiring – this is done by pressing to tabs and pulling off connector
• Other guides say to disconnect the connector for the hazard/DSC switch. I could not get my fingers in so I disconnected the whole centre air vent by unscrewing 2 bolts and un clipping plastic tabs around the centre vent (in green). The centre vent comes away from the trim, place it where it wont get scratched.
• The climate control comes away by gently prising 3 tabs at the top and pull out
• Unclip the 3 connectors – slide the retaining clip over and pull out/push 2 tabs to remove other connector
• Insert screwdriver and gently pry outwards, this is held in with 4 metal pins
• unloop the wiring connector for the heated seats to remove the panel
• undo 4 screws and pull the HU out gently – you may want to shift it into neutral or I took my gear stick off to give you more room. Also lay a towel down not scratch trim (8)
• OEM quadlock on the HU, pull the tab lever to release the connector (9)
• If you have idrive remove the 2 connectors off the oem quadlock and place them in the new harness otherwise you will lose sat nav/telephone voice
• Plug the Technics harness into the back of the HU and the OEM connector into the harness
• Remove the under tray under the glove box – this is held on by 2 torx screws and it slides out. NB - there are further wiring attached to the tray
• Unplug the various connectors (NB after you have unplugged do not start the car as SOS warning light comes up as I forgot to plug it back in as I had to move the car)
• the side kick panel is held on with 2 clips just pull it out by using hands where shown
• The side door foot trim is also held in with 6 clips and will need to pull off (I forgot to take pic of this)
• I originally ran the incoming/outgoing Technics wiring loom under the glove box but as my previous thread I got interference on once channel so had to re route it by lifting the carpet up and going across. I think because the fuse box is there and a lot of wiring I ran it alongside and it may have been causing some interference.
• I undone 4 T45 Torx bits that hold the passenger seat – NB push the seat far forward and upright position as this will help tip the seat back easier. Also becarefull if you have electric seats as not to disconnect the wiring as it may throw up an error code. Once 4 torx screws undone I tilted the seat back and this gave me enough room to remove the sub grill to allow me to lift the carpet up.
• I pulled back the passenger side carpet, this was easier said than done as the carpet was very thick and would not bend easily. I routed both incoming and outgoing looms and cable tied it to the wiring. I used insulation tape around a bend as the plastic was sharp and did not want to damage the cabling. I pushed both looms through hole into centre console and grabbed it behind the HU
• I connected this up to the harness and went back to push the HU back in.
• NB – This was the most painful/soul destroying part (for me) as it took 2 hours of taking the HU out, moving the wires, pushing HU back in and so on. As the space behind the HU is limited I connected everything up and the HU would not push back in because of the extra wires. I was told to move the quadlock up and down through the climate control access panel. I could not get my hand in and cue cuts and grazes on knuckles/fingers.
• In the end me and my cousin decided to cut a small chunk out of the cage to allow for the quadlock to be pushed through to the side – this allowed the HU to slide in back
• The HU was screwed by 4 screws, refitting the heated panel/climate control/centre vent to main trim/connected the starter button etc (reverse of the above)
• I then ran the looms down the passenger side (push the wire down as there is plenty of room) and also connected new wiring (provided by Technic) to the sub. I had to take out the sub as I had no idea which pin was negative and positive (sub comes out by undoing 4 torx screws)
• I then used the jumpers again provided by Technics into the old connector block
• I then Refitted the side panel/side kick panel/glovebox under tray and moved onto the back
• Rear seat you need to pull up as its held with 2 metal clips
• I took off the trim and undone 2 torx bits so I could pull part of the rear door card off allowing me to slide wires behind. I have taped the wires with insulator as there are sharp parts behind the door card. Also note my trusty paint brush comes in handy as it allows me to push the cable in between door card and carpet
• Just a matter of running these cables into the boot – side rear corner pillar just pulls off. make sure you run another cable for the drivers side sub alongside)
• Remove the boot liner/tray above the battery.
• will need to remove loading tray – this is held on with 4 clips just need to pry them out with a screwdriver, and unclip 2 tabs and 2 screws inside
• the carpet over the passenger wheel arch – remove the warning triangle – it is held on with 2 clips (pry out with screwdriver) – undo the plastic surround on the hook held on with torx screw – carpet should pull out
• I decided to run my power cable up and in between boot skin and to the passenger side. I have ran 2AWG running into a fused dizzy block and then 4AWG to the amp. Reason I have done this is I may add another amp later on so wanted to have wiring in place. The fuse at the battery is 150 amps and 100 amps in the distribution block.
• I decided to mount my amp where the CD changer would be. Cue some A-Team music and I cut out a flat piece from MDF and bolted my amp it (I used a cardboard template to cut out MDF board)
• for those keen eyed viewers you will notice I have not used the same colouring earth cable (only because I ran out)
• I screwed everything down/cable tied all loose wires/connected the power cable to the battery/connected up the earth/put all trim/carpet back in and DONE
I need to buy a shallow tray to fit over as the one I have the depth is too big