Very Confusing & Poorly done electrics plus Amp Flow when no obvious termination - CONFUSED

[RAW]

New Merc Van (name to be decided) has a reversing camera which the previous owner said was a drain to the battery and flattened engine battery after approx 1 week. I have tried to figure out what is what and am now very confused so Camera itself & monitor is definitely drawing power when engine is off by the looks as Camera LED's appear to be lit at rear.
I have tried to figure out what is going on and discovered this:

So there the monitor is on and the brown lead has 0.247 Amp flowing through with monitor on.
Then i found the end of the brown lead and took it out of connector block

So the leads that have electrical tape over were connected to the terminal block in picture foreground
I thought this would then stop the battery drain BUT this is what happens next

So with the brown lead effectively disconnected the other end there is still 0.148 Amp through the Lead. Why ? And this will still flatten the battery but in a longer time frame I am guessing ?
AM I missing something obvious as I would have thought a lead that is not in a circuit would be unable to carry current ?

 

[MarkJ]

To ask the obvious, is the meter calibrated? I think that good ones are very sensitive to stray magnetic fields, of which there are probably lots near a dashboard. I understand that you need to place one of these meters where you want to measure something, zeroise it, then place it round your wire or thread the wire through, making sure the meter is in the exact place you zeroised it, and see what happens.

Just a theory!

 

[Nabsim]

Is the monitor actually powered off when engine is off? Never looked at mine to see exactly how it’s been done but it is completely dead until ignition is switched on.
Saying that over winter if mine was left (before I had solar with trickle feed) it would flatten the starter battery in a week or two. Not sure if it still does as it starts fine since changing the battery fir one of the Powerframe battery I took out of habitation bank but I also run genny every couple of days to recharge habitation bank and the mains charger will put up to 3 amps to starter battery.

 

[Nabsim]

As an aside, I often had a problem trying to restart the engine when it was hot. I thought it may be can sensor after a few discussion on WC but had never got round to getting it swapped out. Since I replaced the starter battery this problem has gone away so battery must have been well past it.

 

[RAW]

Is the monitor actually powered off when engine is off?

Nope and there are some red leds on camera that remain on as well, maybe poor UV ones or something

Since I replaced the starter battery this problem has gone away so battery must have been well past it.

Father-in-law said I could get a Free battery test at Halfords so that might be the next step....

 

[RAW]

To ask the obvious, is the meter calibrated? I think that good ones are very sensitive to stray magnetic fields, of which there are probably lots near a dashboard. I understand that you need to place one of these meters where you want to measure something, zeroise it, then place it round your wire or thread the wire through, making sure the meter is in the exact place you zeroised it, and see what happens.

Just a theory!

It is not a high-end meter, just a good quality clamp meter as recommended by Big Clive

Going to bang @wildebus (David) in here as he's not see this thread yet by the looks and may well have something to say.
Not 100% sure (need to check) but don't think there is any VSR or separation between Starter Battery and Leisure batteries, that would make a big difference and would need resolving ASAFP

 

[wildebus]

New Merc Van (name to be decided) has a reversing camera which the previous owner said was a drain to the battery and flattened engine battery after approx 1 week. I have tried to figure out what is what and am now very confused so Camera itself & monitor is definitely drawing power when engine is off by the looks as Camera LED's appear to be lit at rear.
I have tried to figure out what is going on and discovered this:
View attachment 2084
So there the monitor is on and the brown lead has 0.247 Amp flowing through with monitor on.
Then i found the end of the brown lead and took it out of connector block
View attachment 2085
So the leads that have electrical tape over were connected to the terminal block in picture foreground
I thought this would then stop the battery drain BUT this is what happens next
View attachment 2086

So with the brown lead effectively disconnected the other end there is still 0.148 Amp through the Lead. Why ? And this will still flatten the battery but in a longer time frame I am guessing ?
AM I missing something obvious as I would have thought a lead that is not in a circuit would be unable to carry current ?

sounds like maybe the camera is still powered up?
It is possible to get some sprurious reading of current from a clamp meter, and .15A is quite a low current.
As you rightly say, a lead that is not connected will have no current (it will just be a piece of wire) so there would not be any flow, so assuming the meter is reading right (put it on Syvlias battery -ve and compare what the meter tells you with what the BMV is reporting - that will provide a reasonable dregree of calibration info) there is still something connected.

Also sounds like you are saying the Starter and Leisure batteries are directly connected via a cable? that is not the normal way to do things as you know. It would make me want to check if there is any suitable protection (fuses? maybe breakers?) protecting that connection? there must be one at each end for safety and I would suggest that if you have not done so already, you check all the electrical safety aspects before sorting out parastic current draws Having a permanent connection like that, and the use of domestic flex* in 12V wiring would make want to do a thorough check-over.



*There is nothing inherently wrong is using domestic 240V flex in a 12V vehicle wiring, but only if firstly the installer knows what current it can support! too often it is used and the "power rating" is the only consideration ignoring the fact that the same power draw on a 12V circuit is 20x the current on a 240V circuit. Also which is the 12V? Blue or Brown? (Brown is traditionally Ground in DC but Live/Hot in AC - did the installer have a "AC" or a "DC" mindset?

 

[RAW]

Also sounds like you are saying the Starter and Leisure batteries are directly connected via a cable? that is not the normal way to do things as you know. It would make me want to check if there is any suitable protection (fuses? maybe breakers?) protecting that connection?

Yes it is and as far as I can tell no there are not any protection devices
The cable running from +ve vehicle side to +ve Leisure side is pretty hefty 10mm by the looks, the rest of the work is a mixture of not particularly good and often domestic wiring, but there is nothing with particular heavy draw that I can see. Unless the diesel heater or carver water heater (gas) use much power.
I have put another post about battery separation with Victron kit here
motorhomebuilder.com/threads/no-vsr-split-charge-or-anything-else-cyrix-or-battery-protect.66886/

Thanks as always
Robert

 

[wildebus]

...So with the brown lead effectively disconnected the other end there is still 0.148 Amp through the Lead. Why ? And this will still flatten the battery but in a longer time frame I am guessing ?
AM I missing something obvious as I would have thought a lead that is not in a circuit would be unable to carry current ?

I used my clamp meter today for the first time in ages. Initially I thought I had a overhead load on a Victron DC-DC Converter of 0.7A, which is a bit higher than I would have expected.
THEN I noticed that without ANY cable within the clamp, there was an apparent current reading of around 0.6A or so, so clearly not right. I hit the ZERO button (I see yours also has this) and then there was no current in free air, and when I put the meter around the DC-DC converter cable I got a much more expected 0.15A. (I also checked by checking the current on the Inverter when running a 300W heat gun and that recorded a reading that was as expected).

So try it again and use the zero to do a device reading reset and see whayt happens

 

[RAW]

So try it again and use the zero to do a device reading reset and see whayt happens

At the time when I took the pictures I did that, ZEro'd the meter. Did it a few times as could not believe that I was getting a current reading through a disconnected cable. So perhaps what @MarkJ said about field interference might be valid as there is quite a big rat's nest of cabling under there

There's quite a bit of electrical work to do both habitation and vehicle side and here's my list (as a reminder to my head, more than anything else)

• Reversing lights don't work
• Reversing camera stays on
• Additional rear running lights added do not work passenger side
• Short or something flattening vehicle battery quickly (36 - 48 hours), have disconnected cable between vehicle and leisure to see if that helps
• USB PSU by seat failed
• Solar needs overhaul and add Victron kit

Lots to do !!

 

[Nabsim]

If you aren’t using your van at the moment drop one of your leisure PowerFrame battery’s i as starter and see if you are getting the same drop. I have used one of my 3 surplus power frames for this purpose and it’s performing great.
Messes with my head that a battery will no longer perform as leisure battery but is excelling as starter lol. Yes I know the theory of it but still...

 

[RAW]

If you aren’t using your van at the moment drop one of your leisure PowerFrame battery’s i as starter and see if you are getting the same drop. I have used one of my 3 surplus power frames for this purpose and it’s performing great.
Messes with my head that a battery will no longer perform as leisure battery but is excelling as starter lol. Yes I know the theory of it but still...

Took Van to a local Halfords and had all 4 Batteries Tested by them on the Yuasa Tester device
Think it was this one www.hardwarexpress.co.uk/yuasa-mdx617-battery-tester-analyser-4906-p.asp

They all came up as good, Father-in-Law had a quick look and thought there may be a +ve cable shorting something out in dash area

 

[SquirrellCook]

Most of these battery testers are a waste of time for motorhome use. The only way is to do a proper timed discharge test.

I did a post on my experience getting some Varta LFD90's replaced. They are still good starter batteries but useless for leisure use if anyone wants them.