What would you expect a battery drain to be in Amps?

[buzzer]

If you connected an ammeter to the battery with the car locked, and the alarm on, how many amps would you expect to see on the ammeter?

I currently have 0.2 Amps.

[Stu R]

I'd expect to see well under 100mA on most stuff, and <50mA once it's gone to 'sleep' properly.

200mA is a bit high, but still a fairly small number.

[buzzer]

Stu R said:

I'd expect to see well under 100mA on most stuff, and <50mA once it's gone to 'sleep' properly.

200mA is a bit high, but still a fairly small number.

Thanks. I will see how it goes, fitted a new battery today so it may have been that was not up to scratch.

[anonymous-user]

My wife's Z3 is 180ma, it's a pain as she uses it as a third car, (like every alternative sunday), and it will drain a battery if not used one week, long term plan is put a relay in all the circuits draining power, as we don't need the alarm etc, and all we lose is the time on the clock, but as a short term I've put a simpe screw disconect on the battery, fiver off ebay and absoluty great.

[buzzer]

well, after a bit of investigation, the dash cam was pulling 0.15A so I have a switch on it now when its in the garage.

interestingly, it takes around 5 mins for everything to shut down, initially its as high as 6A, and then it drops in increments as everything goes to sleep.

It also draws less current when its locked and the alarm is on, which is opposite to what I would have expected.

Also turns out I had the wrong battery on it... Someone in the past had fitted the standard battery for an SLK, the AMG version is quite a bit higher specification.

[Stu R]

Glad you've got it sussed, they can be a pain to find.

It's fairly normal for higher current draw just after shutting it off, then going into 'sleep mode' after a short while once it's shut off its various modules etc, especially on newer stuff.

[Matt Seabrook]

Some of the modern stuff can take 5-6 hours to power down properly after that about 30m amp would be about right.

[Nighthawk]

Most manufactures have a limit of .5amp draw with the vehicle asleep, typically sub .2 with no extras to manufactures spec.