Finally found a solution to remove the dreaded Bluetooth pop and high volume on low settings on the D5151. Heres how:
Total Cost: $3 from Jaycar
Total Time: 30-45 mins
Likely to void warranty, if your ever thinking about sending it back to China for repairs.
What you will need:
- 4x Male RCA connectors
- Sidecutters/wire stripper
- Soldering iron and solder
- Heat shink
- Tape
Wiring colours are as follows:
(Speaker): (Positive)/(Negative)
Front Right: Grey/Grey black
Front Left: White/White Black
Right Rear: Purple/Purple Black
Left Rear: Green/Green Black
Aim: Fit male RCA plugs on the eonon loom, which plugs into the factory loom to the bose amp. Use the eonon line outs to feed the bose amp.
- Remove the D5151 and unplug the cables from the rear
- Snip each colour pair on the eonon loom, up close to the small end which plugs into the head unit (Photo B), so you have plenty of wiring to play with.
- You can optionally snip the small cable tie at the main loom end to give more free play with the cable, also helps when grouping them back together at the end
- Strip the end of each wire and then thread the RCA socket cover over the two wires
- Solder the RCA plug, with the Positive wire on the centre pin of the RCA. (Photo A) The easiest way is to 'tin' each RCA post and stripped wire end, then hold and solder.
- Repeat for the remaining 3 colour pairs
- Cut 8 small pieces of heat shrink to cover the exposed cut off ends (Photo B)
- Group and tape the 4 new cables together down near the main loom plug so the cables sit together nicely
- Fit the eonon loom back to the head unit and plug each new Male RCA from the eonon loom into the corresponding Female RCA on the head unit. Cables are labelled FROUT, FLOUT etc. (Photo C)
- Tape together the RCA's to prevent them coming apart
- Install the head unit and enjoy adjustable low volume and no Bluetooth pop!!
Credit to theblooms on mazda3forums for the idea and wiring colours.