Technical Stereo wiring question

Currently reading:
Technical Stereo wiring question

larkim

Established member
Joined
Apr 10, 2006
Messages
324
Points
169
Location
Frodsham, Cheshire
Hi

Now that I've got the old stereo out of the Multipla, I'm in the process of putting a new one in.

I've bought a sony BT2500.

The old stereo was wired with an ISO harness, and the stereo came with the right adaptor for the aerial.

The only problem I've got is that the new stereo doesn't seem to turn on unless the ignition is turned. The standard fit stereo could be powered up whilst there was no key in the ignition, but the new one doesn't do this. I have the same stereo in my Barchetta, so I know it "should". I've tried switching around the live / switched live cables on the harness (as suggested in the manual), and even managed to blow a fuse by trying the third option ("for cars without ACC stage on the ignition").

Any suggestions about what I might be missing? Electronics isn't my strong suit, but I'm sure I can get this right.

Thanks!

Matt
 
I have that as well, replaced the radio and it only works when the car is running.

funny really

FNG
 
My conclusion is that the issue is stereo specific.

The VDO head unit that was factory fitted in my Multipla appears to be capable of being fully powered from the battery live, but also has some features that respond to the on and off with the switched live.

On the contrary, my Sony BT2500 draws only power to retain settings etc from the battery live, but powers all of the other features only from the switched live, meaning that I can only run the BT2500 with the key turned.

I could I suppose wire both the switched live and the battery live together so that both are powered permanently (this must be how it is in my Barchetta, which has the same HU), but I can't be bothered (!) and SWMBO wants to have the lazy option of "engine off / stereo off", so I'm not going to pursue any further.

I guess I can see some logic - perhaps "decent" stereos are more power hungry, and you don't want your battery draining.

Anyway, just as a final point on this. The multipla's wiring loom is the wrong way round for the switched and the battery lives. The harness that came with the Sony allowed for these two to be switched (the instructions said some manufacturers do it one way, others do it the other), so I guess most installations will need these two wires to be swapped.

Matt
 
I also had this problem and solved it by running a small cable from The ISO connection (on my radios instructions it was numbered 1 to 8 going odd numbers on top of connection and even at the bottom) no2 being a feed form the battery and no7 coming from the ignition circuit this one I cut and then took a short jumper cable from no2 and linked it to 7 now my radio can be listened to with the key out of ignition I just have to remember to switch it off
 
Back
Top