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Constant 0.3A drain

2406 Views 7 Replies 6 Participants Last post by  BJT
Hi all and thanks in advance to everyone that will (I know) do their best to answer my question. Which is:

On the info panel (zig unit I think they used to be called) I have a button that when pressed tell me the Amps I am using at that given moment.

It seems to work ok, each light is about 1 amp, which with my limited knowledge would seem about right.

As I turn things on & off the the reading changes as I would expect. So the general function of the meter seems ok.

But. with all the sub-switches off, the alarm off and nothing that I can see, think of or find to be ON, the amp meter is reading 0.3A.

Which might seem no big deal, except that if it is a true reading would explain why the battery is not holding it's charge as it would be losing 8amps (0.3 x 24hrs) per day, or roughly 10%, which in turn I believe could be the reason that I think the battery needs replacing.

But I can't replace the battery until the 0.3a puzzle is solved.

So my question is 2 fold:
1. is powering the panel & amp meter LEDs taking the 0.3A? Hence it's not really drawing 0.3a all the time only when I check.
2. what could be drawing that power? It's nothing obvious.

Many thanks

PS. I think I could to put a meter across the battery but I thought I'd get some extra info as the MH lives away from home.
1 - 8 of 8 Posts
Some if not all could be the gauge taking the power.
If you are reading the starter battery you will be seeing the memory for the radio and a draw for the engine E.C.U
If its the hab batt it could be the anti freeze dump valve on the boiler taking the current.

Hope this helps
I thought I'd covered everything :oops: ...... It's the Hab battery.
On my van i must select off on the fridge, if i leave it with 240 selected but no hookup it uses power, it must be the selector itself.
Check the reversing camera if you have one. The screen could be powered from Hab or Engine battery but rear view cameras are often patched into the hab battery to keep cable runs down. I overcame this constant drain issue by fitting mine via the spare switch on the control panel so I can turn it off when not on EHU.

And bear in mind that ones activated by engaging reverse might only switch the monitor on yet the camera may be on all the time. Depends on how it was fitted.
jimbo_hippo & sideways

2 very good points, I'll check them both on my next visit to the MH.
0.3A is pretty normal drain with the control panel switched on. Mine is 0.2A, 0.3A when backlit when you press a button. 0.0 when you switch it off and check with a multimeter. So:
1) Yes.
2) See 1)

If you think you have a constant drain on the battery the only way to check is to diconnect the battery at the +ve terminal and use an ammeter in line between the battery terminal and the lug you have disconnected from the battery. Use crocodile clips on the test leads so that you can leave the meter in circuit, make sure the meter is set for the correct load and voltage first, then and remove fuses from the MH habitation fuseboard to see if the load disappears. You may find it is a clock, alarm, or anything similar. At least you will know what is the cause of the battery load; even though you may discover that it is a static load that you cannot isolate. Once found, if it is a non essential item you can decide your next move. You might be able to put a switch in the final circuit of the load, but not if it is an alarm or similar.
Hope this is of some use.
1 - 8 of 8 Posts
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