Sony Radio in Xantia

acrowot · Post by **acrowot** » 13 Aug 2003, 05:40

I have just fitted a Sony CDX-750XPLOD and Autoleads interface for steering wheel controls into my Xantia, all seemed to work OK at first untill I increased the volume, it then blew the permenant 12V supply fuse. This fuse is rated at 2amps ( it also supplies the clock and I/R sensor). I increased this fuse to 4Amps and then 7.5amps with the same effect although I could increase the volume further with each uprate of the fuse. It now has a 10Amp fuse in and the radio seems to be functioning OK. I have tested the supplies with a test meter and they are correct,on the ISO block the ignition switched supply goes to the red wire and the perm 12v to the yellow wire. I can reverse these two wires and the radio does not then blow the origional 2Amp fuse, but all settings are lost on switching off the radio. It seems to me that as the volume is inreased more current is required and this is being drawn from the permenant supply and not from the IGN switched supply which has a larger current rating. Does anyone know if it is the permenant supply that supplies the power for the Radio as I thought it only supplied power for the memory.
John
Xantia 1996TDSX

blueboy2001 · Post by **blueboy2001** » 13 Aug 2003, 06:00

Ahh, the infamous 2A fuse problem! Both myself and Fox have had this problem when we fitted our Sony HU's. It does seem that when you use the Autoleads box and a Sony HU, it draws its running power from the permanent live, and the switched live only triggers the unit on and off. Oddly enough, the owners book specifies a 5A fuse for the perm live/clock, and since changing mine to a 5A I've not had any trouble (mines a CDX MP40).
On mine, the back of the HU has a 10A fuse fitted, so fitting a 10A fuse in the fusebox should be ok. The wiring seems to be standard guage stuff, so it shouldn't have any trouble handling the current.
I'm not sure if Sony units all behave in this way, or its a quirk of using it with the Autoleads harness.

acrowot · Post by **acrowot** » 13 Aug 2003, 06:22

Thanks for your reply blueboy2001, my handbook rates this fuse as 2amp and it was a 2amp that was in, my HU has a 10 amp fuse on the back of it and I would have preferred something a little less before it. I dont think the Autoleads interface interfers with the supply voltage but I am not sure and I do not want to take the HU out to check, I just thought it was odd to power the HU via the Perm supply, I was begining to think the HU was faulty, I should sleep better after your reply.