After market stereo wiring


Registered User
Dec 13, 2013
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Hi all

Mods: happy for this to be moved to ICE but 8L knowledge is great here hence the questions!

So bought a kenwood double din to fit into my 2003 1.8t sport. I bought what I thought was the right harness (CT20AU09).

First problem was there was no power to the head unit. After a lot of searching I learnt that I need to wire in an ingnition live. So first question, is which fuse is best used. The usual suspects of cig lighter or internal light doesn't work well as the unit stays on permanently. I want the unit to switch off with the removal of the key. I am currently piggybacking off the washer fluid/wiper motor fuse (number 24) but the unit is not holding its memory.

Question is: Can anybody recommend a fuse I can piggyback from to make it all work properly? I am worried/scared to use something significant like engine timing or similar.

Secondly, the rear speakers are no longer working? I assume it's because the rears are amplified, but is there anything I can do to make them work?

Thank you!
Hi mate,

With regards to power supply there is a permanent live in the oem plug to the stereo and to wire in a 'switched' ignition live,for my aftermarket bluetooth I used a spare fuse from the fuse panel,you could use that one and insert the correct fuse for your aftermarket stereo...

For rear sound,you may have the wrong adaptor (I can't comment on the right one as haven't done it myself) but there are three types of sound system in our cars...

non bose
half bose
full bose

I'm sure someone who knows more will offer their knowledge.