Parasitic draw on 3 fuses :(

[samZ4M]

Hi all,

I have noticed my Z4M battery slowly goes down if I don't trickle it, so decided to try and tackle the issue. Figured something was drawing down, so I set about pulling all fuses until I found it.

Seems I have an issue on 3 fuses, each one will pull just under 1amp with the car idle and door latches latched.

#26 1.08A (interior lights)
#49 1.20A (nav/tv)
#50 1.06A (radio)

Without the 3 it's about .35A. With all in it's about 2.2A.

I decided to tackle #26 first, as it's just interior lights, but I've pulled every light I can find and it's still drawing from the battery. Does this mean a cable is shorting somewhere?

I have a Intravee II and a gap-Tech as the only modifications to the car. Disconnecting both and I get the same drain, so that rules them out.

Any other ideas?

 

[Rockhopper]

Light in the arm rest storage as well?

 

[Rockhopper]

Also don't forget that some systems will take many minutes to shut down after you lock the car. In our Puma it might be twenty minutes till things stop buzzing!

 

[samZ4M]

Not found that one, so will take a look.

I disconnected the battery and left it 30 mins before testing. It’s did find it funny that when you runs test you’re ultimately connecting the battery back up. Do you have to wait 30 mins after every amp check?!

 

[axelleveau]

Hi Sam,

there is probably something wrong with your test procedure. As an indication, vampire drain shoud be in the order of 100mA, maybe up to the 0.35A you measured but clearly those 3 fuses indicate systems that are not sleeping and that kind of drain would kill your battery in less than a week. Whether it is because you have not left the car off and locked for long enough or there is a genuine software or communication issue preventing some systems from sleeping (I recently had a dead battery because my radio got stuck on "phone" after I took a call through the car bluetooth) can only be figured out by taking your time and doing more measurements.

 

[samZ4M]

I have double checked and those are the figures, I can't get it lower! I also double checked it was just an alternator issue, but it's not, would almost be preferred as it's a few bolts and a replacement.

Think I'll take it to a auto electrician in the new year, for now it'll be on trickle, I only use it once a week to turn it over.

 

[Rockhopper]

It'll take a good thirty minutes of running to put back in to the battery what it took out to start the car. Maybe thats why its going flat?

 

[kis]

I have some sort of parasitic draw too. Have nav as well. Always had the intention of looking into it but just keep it topped up. In fact my battery is probably pretty knackered but kind of refuse to buy a new one, when I know I’ll end up breaking it sooner or later if I don’t keep it topped up.

Please do let us know your findings!