Posts: 1
Joined: Mon Sep 26, 2022 4:36 pm
Delivery Date: 26 Sep 2022

Parasitic draw on 12v battery

Hi everyone, My 2013 Leaf has a reoccurring problem where the 12v batter is drained in a week or so. Battery already replaced. The dealer has diagnosed a "parasitic draw" back to the audio unit and wants to replace with a new $2800 unit, not sure the car is worth that much. This is a basic short trip commuter and since his diagnosis leads to a specific fuse. What are thoughts on just removing the fuse? Any problems that might be associated with that?

Thanks in advance
Posts: 1886
Joined: Tue Aug 01, 2017 3:33 pm
Delivery Date: 01 Aug 2017
Leaf Number: 311806
Location: Boulder, CO

Re: Parasitic draw on 12v battery

Obviously you will lose all the functions of the audio and whatever other circuits are powered by that circuit. If it's only the audio on that fuse (quite possible) and you don't care about the audio then removing the fuse should fix the problem and cause no other side effects.

It might be possible the lack of communications with the radio will get logged by the car's central computer but I don't think it would generate a CEL so no worries there either.
Gold Member
Posts: 3416
Joined: Mon Nov 22, 2010 6:47 pm
Delivery Date: 12 Jun 2011
Location: Phoenix, AZ

Re: Parasitic draw on 12v battery

It is probably the fuse that supplies power for the memory and other functions in the audio unit while the car is off. If so, then the unit will still function when the car is on, but will start up as if the battery was disconnected for a while. It may set some DTC's (diagnostic trouble codes) for the audio unit, but should not cause any other issues and will not trigger the MIL (malfunction indicator light).

Since you note replacement cost as $2800, I assume it is the navigation system in an SV or SL. If so, you might be able to eliminate the parasitic draw by disconnecting and removing the cellular modem that is probably no longer able to communicate (probably 2G or 3G modem instead of 4G LTE on current cars).
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015; traded 8/10/2019 at 82,436 miles
White LEAF 2019 SL Plus purchased 8/10/2019

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