Head unit battery drain

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Buzzard897

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Hi, bought the car recently and had a problem with my battery going flat overnight, I’ve chased the fault to the head unit (current draw check) and realised their is only a permanent live. The unit is a pioneer MVH double din series, does anyone know how I’d go about adding an ignition live as I would need the permanent for the memory surely? Could be talking **** here but that’s how I understand it. I can take an ignition live from the fuse box that’s no problem just where to put it on the stereo end? thanks
 
I had the exact same problem with my RNSE, i think the standard wire looms connect it to perm live for some reason - this means you can switch your radio on without the key in the ignition.
It cost me a battery and a few jump starts to figure out what was going on. I cut the loom at the back of the radio and wiring in a switched live from the fusebox - that way the radio will only switch on when my ignition is on - not had any issues with battery drain since
 
Cheers for your reply, yeah I think I’ve killed this battery too shame because it’s practically brand new by the looks of things, did you have any problem with losing your settings on the unit eg. clock, speaker settings?
Cheers
 
Interestingly enough no, i guess there is some kind of internal battery in there to remember these settings.

I have found an issue with my GPS though. I think it may have been resolved now as I have changed the postion of the GPS receiver closer to the window.

As the system boots up it takes a while for the GPS location to be updated on the map, an issue i didn't have before my unit was on perm live..
 
My Rnse has perment live and i havent suffered any battery drain at all , take your unit out and read wire diagram on top and see if you have all the wires firstly in the correct pins , or do an autoscan done and see what faults come back as it could help you trace problem
 
audi upgrades
Issue I was having was when my RNSE was off, I would still hear the fan ticking over, when that stopped eventually I would hear it switch on randomly and hear the navigation disc spinning but the screen would stay off. I reckon it was doing something in the background but it must have kept doing that a lot as the following day my battery would be dead = no good!
 
MA3TDIQ said:
Issue I was having was when my RNSE was off, I would still hear the fan ticking over, when that stopped eventually I would hear it switch on randomly and hear the navigation disc spinning but the screen would stay off. I reckon it was doing something in the background but it must have kept doing that a lot as the following day my battery would be dead = no good!
Click to expand...
As far as i sm lead to believe if fitted correctly once you remove key from ignition this switches rnse off so it doesn't randomly switch on so i think an Autoscan then check wiring is pinned correctly would be a good start .plus the guy could try recharging batteey
 
It’s a pioneer mvh-a200vbt mate, I shall do what you said tomorrow and see where it gets me. Thank you
 
fair enough, an auto scan is always a good idea. I just got fed up with my battery constantly die-ing so far me the best fix was ignition live for the radio and have had no issue since..
 
ch1z64 said:
I would take a stab that it hasn't been wired up correctly
Click to expand...

How could you get the wiring wrong when its just a quad lock? What specific things could be wrong causing the drain?
 
MA3TDIQ said:
How could you get the wiring wrong when its just a quad lock? What specific things could be wrong causing the drain?
Click to expand...
Firstly i would check that it is a original audi quadlock which would be wired either for symphony + or Rnse depending on age off car . Thats why so many people have problems with fitying aftermarket HU's as there not just a straight swap mostly
 
Why do you thing itsthe unit causing drain , just that i did a silly thing the other day and added 2 10amp fuses to empty dlots so i knew where a terminal 15 + terminal 30 for dashcam and i had been doing something to my rnse looking for bose pin and moved what i thought was bose pin left car over night and came out to very low voltage battery . But when i removed the 2 fuses and put pin back + charged battery i now have charged battery and no drain , soit coupd have bedn the fuses or the wire
 
Used a multimeter and unplugged the unit and it went down to 0.05 amps from 0.70, 100% sure it’s the head unit/wiring.

as for the unit, yeah it’s alright thinking about swapping it out for a Apple car play unit though but they’re a bit much imo unless you know of any decent cheaper ones?
My standard unit was an concert i believe and I bought the quad lock adapter on eBay for about £15
 
I'd love all the bonus's of car play and dab but i hate the idea of losing all the info on the dis so i've just kept my rns-e. Also from some of the above comments, if you switch off your radio and ignition off and sit in your car for a while you should hear everything shut down i.e fan on hu stopping etc. but if you then open a door it'll all come back to life as the car wakes up but then should shut down again after doors closed and locked,iirc usually around a minute or so.
 
Buzzard897 said:
Used a multimeter and unplugged the unit and it went down to 0.05 amps from 0.70, 100% sure it’s the head unit/wiring.

as for the unit, yeah it’s alright thinking about swapping it out for a Apple car play unit though but they’re a bit much imo unless you know of any decent cheaper ones?
My standard unit was an concert i believe and I bought the quad lock adapter on eBay for about £15
Click to expand...

It could be the wrong wiring harness/quadlock connector for your car as that unit could be used in any car or it could be a faulty harness or a bent over pin or something.
Something you could try. On the wiring harness of the unit see if you can figure out which is the permanent live cable and which is the switched live (acc) cable. If you can find both of them then try and swap them over(ideally unpin them and swap them over or you could cut them and join them) and then see what happens. If they’re the wrong way round it would cause battery drain.
I’m not saying that’s your problem but it’s possible.
 
Matt268uk said:
I'd love all the bonus's of car play and dab but i hate the idea of losing all the info on the dis so i've just kept my rns-e. Also from some of the above comments, if you switch off your radio and ignition off and sit in your car for a while you should hear everything shut down i.e fan on hu stopping etc. but if you then open a door it'll all come back to life as the car wakes up but then should shut down again after doors closed and locked,iirc usually around a minute or so.
Click to expand...

I agree with that, the DIS info is far too handy to loose! Is there not an aftermarket unit that connects with DIS?
 
@MA3TDIQ i've spoken to a few car audio specialists and from what i've been told there are no aftermarket units that will connect to the dis. They tell me that as the head unit's show all info on their screens so no need to try and configure them to the many different car brands currently sold.
 
If you don’t have the right level of gateway module matched to the level of RNSE you are using then this would be the cause of battery drain since factory built vehicles obviously don’t suffer with the aforementioned issues.

There is evidently a mismatch somewhere... just because some ECUs support retrofitting by changing parameters in VCDS does not mean their emery single software logic is entirely inter compatible (hence your drain issue).

They use CAN bus to sequence with no issues.
 
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