Parasitic Draw from Avin Avant 4?

[AWE46M3]

My battery died shortly after my Avin Avant 4 head unit was installed. To be fair, my lead acid battery was 5 years old, and I did leave my key in the ignition while working on my front end, so I suspected my battery issues would be resolved with a replacement.

I recently installed a new AGM battery (H7) and let the car sit from Thursday until today. I drove the car for 3 hours on Thursday and believe the battery was fully charged by the time I parked it for the evening. When I went to turn it over this afternoon, it hesitated quite a bit before firing up. I’m convinced my Avin head unit is draining my battery - Has anyone had a similar issue? I would let the car sit for multiple weeks without driving it when I had the factory business unit installed and never had rough starts.

I was digging through settings and enabled the battery reading feature on my Avin Avant 4, which read 13.3-13.5 at idle. 12.5v with the car off in accessory mode.

I turned off the auto-sleep feature and set the setting to 30 seconds to see if I can get the unit to turn off quicker. From what I’ve read, it stays on slightly (which is why it boots up so quick) and I believe this could be one of the contributing factors.

I’m getting close to swapping this thing out and want to see if I can squeeze a couple more months out of it. Any help I can get to verify parasitic draw from the head unit would be much appreciated.

[Chanman1029]

Have you tried to do a parasitic draw test with a multimeter? That would tell you exactly where the draw is coming from. Once set up properly, by process of elimination you can pull fuses from the fuse box, and once voltage on the multimeter drops, boom, you found the source of the draw.

[Bent_Remy]

My battery died shortly after my Avin Avant 4 head unit was installed. My lead acid battery was 5 years old, and to be fair to my Avin, I did leave my key in the ignition while working on the front end and drained the thing completely.

I recently installed a new AGM battery (H7) and let the car sit from Thursday until today. I drove the car for 3 hours on Thursday and believe the battery was fully charged by the time I parked it for the evening. When I went to turn it over, it hesitated quite a bit before firing up. I’m convinced my Avin head unit is draining my battery - anyone had a similar issue? I would let the car sit for multiple weeks without driving it when I had the factory business unit installed and never had rough starts.

I was digging through settings and enabled the battery reading feature on my Avin Avant 4 and it read 13.3-13.5 at idle. 12.5v with the car off in accessory mode.

I turned off the auto-sleep feature and set the setting to 30 seconds to see if I can get the unit to turn off quicker. From what I’ve read, it stays on slightly (which is why it boots up so quick) and I believe this could be one of the contributing factors.

I’m getting close to swapping this thing out and want to see if I can squeeze a couple more months out of it. Any help I can get to verify parasitic draw from the head unit would be much appreciated.

I have the Avin A4 head unit in installed in my E46 for a couple of months now and I'm not seeing any issues like this. My car sits for 1-2 weeks between drives and she always fires right up and idles fine. At 5 years old your old battery was probably on the way out anyway. I'll be following to see if others are having a different experience.

[AWE46M3]

Have you tried to do a parasitic draw test with a multimeter? That would tell you exactly where the draw is coming from. Once set up properly, by process of elimination you can pull fuses from the fuse box, and once voltage on the multimeter drops, boom, you found the source of the draw.

Never done this test personally but I'll see if I can figure out how to DIY this. I'm sure this is easy enough for any reputable shop to do as well. Thanks for your input

[AWE46M3]

I have the Avin A4 head unit in installed in my E46 for a couple of months now and I'm not seeing any issues like this. My car sits for 1-2 weeks between drives and she always fires right up and idles fine. At 5 years old your old battery was probably on the way out anyway. I'll be following to see if others are having a different experience.

That's good to know. I agree - the old battery was done. I was really surprised by the start hesitation on the new battery. I'm going to figure out which fuse needs to be pulled and see if I can verify the Avin as the culprit.

[Chanman1029]

Never done this test personally but I'll see if I can figure out how to DIY this. I'm sure this is easy enough for any reputable shop to do as well. Thanks for your input

Any shop can do it, but its also so easy for you to do it yourself, dont waste your money on them.

[Shonky]

The main issue with a current draw test through say a 10A range on a multimeter is preventing the car waking up as a bunch of modules, lights etc will draw a fair bit of current. An SMG will pressurise the hydraulics etc. Not hard to insert a meter in series without disconnecting. For reference my stock vehicle with just a BlueBus sits about 19mA when asleep. Spec is <40mA


Alternatively just measure voltage drops across the fuses. You have a suspicion as to which device it is already so that narrows it down to just those fuses. It may be hard to find smallish loads with this method though.

[Riley]

I have an avant 4 in my car and it sat over the winter for probably a good two months and had no battery issues. Last replaced my car battery about a year and a half ago now.

You replaced your battery with a new one but did you check your alternator charging voltage? That could’ve been what killed your old battery even if it was 5 years old.

[AWE46M3]

I have an avant 4 in my car and it sat over the winter for probably a good two months and had no battery issues. Last replaced my car battery about a year and a half ago now.

You replaced your battery with a new one but did you check your alternator charging voltage? That could’ve been what killed your old battery even if it was 5 years old.

Thanks for your input - I did a bunch of testing today and I believe my Alt is in the early stages of failing. It is at 13.1-5v when I'm driving. It should be closer to 14. I purchased an alternator in December and have that on my preventative maintenance to-do list. I plan to get that swapped out in the coming week. I'll bump this thread after the alternator job.

[Riley]

Reply. Fingers crossed it solves your issues. Still wouldn’t be a bad idea to check for drain from the radio too.

[Shonky]

Low 13v is not great from an alternator but should generally be enough to keep things charged. I'd still say you have a current draw. Perhaps it's the alternator.

[AWE46M3]

Failing alternator confirmed. No considerable parasitic draw to speak coming from the Avin. Updated the shut off setting from auto sleep to 5 minutes. Don’t care if I have a slower boot time - want to be certain that half asleep/half awake state the Avin is in does not drain the battery.

Thanks everything 🤝