YES I HAVE SWITCHED (and re-switched) THE RED AND YELLOW WIRES. It makes no difference. It seems that there must be power on both lines or it sleeps/powers off. Its clock display works so I know it's maintaining power once the ignition key is removed.

 

Unit is

 

KD-X330BT glossy

 

KD-X330BT Manual

 

The JVC loom includes an extra bullet connector on the red wire. So I assume I could use that to provide both 12V feeds to the unit constantly?

 

BTW: Despite recently linking a most excellent youtube video on how to replace pins in the loom. Getting pin 5 out of the factory loom proved long-winded. The black "power" ISO block on the Fabia loom contains a locking bar. I hadn't spotted it as it's flush and discrete, despite being bright orange in an otherwise black connector! A small flat baded screwdriver or similar is needed to persuade it to move. Then all of the pins one has been dicking about with fall out at once!!!! I needed a torch to spot the locking bar and see how to use a screwdriver to start removing it.

 

Pin 5 needed to "die" as Skoda use it as a 20A live feed if you've the factory SATNAV. I needed the spot for my aerial booster and the amplifier on/off.

 

J.

Most aftermarket stereos work in the same way, requiring keys in the ignition to work

I actually bought it as the factory h/u started going on the blink. Need to add an "I thought" to the previous sentence....The same power "fluctuations" seem to be affecting the new setup. It would randomly shut down, then SAFE and relearn..... or not.... Tonight I've discovered loose connections on the under-bonnet fuse holder (aftermarket ICE thing, not the Skoda one). So maybe when I go out to setup the radio tomorrow it will behave.

 

I much prefer the JVC. It is mechless plus Bluetooth plus USB plus an actual EQ.

Most aftermarket stereos work in the same way, requiring keys in the ignition to work

 

This is the case, the OEM unit continues to work because software in the unit will maintain power using the unswitched line for about 30mins before it also turns off. Most aftermarket radios do not have this logic, so will always require the key in to work. I say most because some do, eg. from what I recall my old Blaupunkt Woodstock DAB would run for 30mins before killing power.

 

If you attempt to bypass this so the radio will always run by using two always on 12V feeds then you risk the battery running flat because (A) you may forget to turn the unit off when leaving the car and/or B. the unit does not fully power off unless the switched supply kills power, for example to keep the bluetooth alive etc.

Edited 15 September, 20169 yr by mannyo

Fingers crossed, my tightening up the amp fuse connectors seems to have stopped the amp from dropping out.

 

Ha! Which means I have a Symphony CD in the lounge that's not broken. Shame it's "smart coded" and I can't recall ever having had a PIN slip for it.

If you want a headunit that can be turned on without the ignition you need to make sure the head unit supports this feature.

 

The only way round the issue is to have the stereo permanently on by using a live feed for both the switched live and permanent live and then manually turning on and off your stereo when you get in and out of the car. This is not ideal though and could cause battery drain issues. (just noticed this has already been mentioned)

Edited 15 September, 20169 yr by SuperbTWM

Could always build a simple circuit consisting of a momentary button, timer and a relay. Then if you want to use the stereo you can use it by pressing the button and it'll turn off after the set time. This will also prevent battery drain.