Mystery 300 milliamps...

[timhowes]

I've just changed my electrics around a little so that everything in the van comes off the solar controller's load terminals - mainly so that my smart little meter plugged into the solar controller can tell me income vs expense real-time!

Now when I say "everything in the van", all I have is a loom which plugs into the fuse panel beside steering wheel (top row from left: 1st, 6th, 7th, 8th), plus the compressor fridge. Nothing else wired up to the load terminals. PV panel terminals and LB terminals wired up appropriately.

When everything is powered down, my meter tells me that 0.3a is still drawn across the controller's load terminals. Fridge is unplugged. When I remove the loom wire from fuse position #1 this current disappears. This seems to power interior lighting but also the stereo - which also seems to need the loom wire in fuse position #8 to function. The stereo is an aftermarket install (predating my purchase of the vehicle), which has lots of functions, but is powered down with all LEDs off.

As you can probably tell my knowledge surrounding this area is limited! But can anyone please suggest where my mystery 300 milliamps is going? Or an appropriate approach to diagnosing the issue?

Thanks in advance, as always

[the1andonly]

this originally came from Geof

fuse 1
That fuse covers an awful lot of things, not just the light!
X03-8
10 Amp
30 Engine - Control System - WL-TAT
32 Engine - Control System Ignition - FE-E
38 Engine - Control System Ignition - J5-DE
82 Air conditioning - Auto A/C Control System & Heater - WL-T, FE-E, J5-DE
90 Chassis related - EC-AT Control System - FE-E, J5-DE
100 Interior lighting - Cargo Room & Spot Lights - WL-T, FE-E, J5-DE
102 Accessories - Audio System - WL-T, FE-E, J5-DE
104 Accessories - Car Navigation System - WL-T, FE-E, J5-DE
108 Body - Power Door Lock System - WL-T, FE-E, J5-DE
116 Body - Auto Free Top - WL-T, FE-E, J5-DE
124 Body - Sound Warning System - WL-T, FE-E, J5-DE

Ie The ECU amoungst other things which is why you cant start the car with a flat LB
The ECU does monitor some things with the engine off, but may be temperature related so does not drain all the time. eg the scav fan (if already on) will stay on after engine off for a given period.

[g8dhe]

That current will be supplying, ECU backup, radio backup, immobiliser, remote fob receiver, all the small computers (aft, side door and several others) even so 300mA is a bit high but quite possible.

[timhowes]

I don't have remote central locking or an immobiliser fitted. Does it sound as though there's a problem somewhere?

[Bongolia]

MPPT or PWM controller?

[timhowes]

MPPT

[Bongolia]

OK, I may be barking up the wrong tree here as electrics remain one of life`s great mysteries to me
Others on here will know but does the MPPT controller itself not draw from the battery in order to operate whereas the PWM draws from the panel?
Anyone?

[wonkanoby]

what makes the radio..recall some lidl ones were drawing a lot

[g8dhe]

I don't have remote central locking or an immobiliser fitted. Does it sound as though there's a problem somewhere?

Not sure a problem as such but I would want to understand what is drawing the current like yourself! I presume your using the Controller display to show the amount of current drawn ? Might be worth using a meter external to the controller which has greater accuracy to start with as most digital displays are always ±1 digit so you could be at 0.2Amps, the problem comes in breaking the loom down to anything less than what is on the 10Amp feed, about the only way to do it is to unplug the known devices, like radio, ecu etc. and monitoring the current as you go.

[windywatson]

Hi,
300ma is nothing to worry about. There are a number of radios on the market that whilst switched off draw similar amounts of current. I've had to get rid of an Aldi radio as that was drawing enough to flatten a leisure battery on it's own within 2/3 weeks whilst the van was stood. When I worked at Brownhills motor homes we often had to check current draw when customers complained of batteries going flat whilst " Van not in Use". As a rule of thumb anything up to 400ma was acceptable dependant on equipment installed. There are many electronic devices commonly installed in vehicles that draw small amounts of current whilst supposedly being switched off. Adding a few of these up soon starts to give larger than expected currants.
I wouldn't be dually worried about that amount of draw. But you could start to isolate individual bits of equipment and monitor the current to see which the culprits are. To combat the small draw that would eventually flatten my battery as the van could be stood for weeks without use. I installed a small solar panel to keep it topped up, Job done.

Cheers

[timhowes]

Thanks everyone. The radio is a Pioneer FH-X720BT, for what it's worth...

I have recently installed a 100w panel on the roof so should have plenty of PV activity to offset this drain and prevent flatting the LB on the driveway, even in the depths of winter (I hope?!)