Power Magic Pro not turning back on when ACC+ power resumes

[WaterHole]

Hey All,

Just got the BlackVue 650GW 2channel. I've installed it correctly to my BMW, direct to the battery with the ACC+ connection going to a fuse which switches off.

The camera works fine. I've wired directly to the battery as BMWs cut all power to sockets after approm 10mins of locking the car. The red wire does to the fuse for the cigarette lighter sockets, which turns off correctly.

The unit is correctly installed, and I have multimeter so have tested all connections. The PMP correctly turns off after the given time.

However, after time out (say 6hours) when power resumes it does not re-start the PMP at all. I have to switch it off and back on again.

Any suggestions? If the PMP faulty?

 

[Deleted member 46308]

Welcome to the forum WaterHole

 

[jokiin]

Doesn't resume when you start the car?

 

[WaterHole]

Hey all.

No, it doesn't start at all. Engine start, or ignition it simply doesn't turn back on until you turn off the PMP and back on again.

 

[jokiin]

Did you check the accessories circuit is live at power on, late model BMW's disable circuits if it sees a load that shouldn't be there, it may well be that its faulty but best to rule the car out of the equation first

 

[WaterHole]

Here's a pic - I've tried to comment, and I've plugged my phone charger in so you can see it is live (rather than my blackvue). The fuse indeed drops voltage after 10-12mins, and come back live when you unlock the car.

 

[jokiin]

what voltage do you get on the meter when you turn it back on?

 

[jokiin]

also what cutout voltage have you set on the PMP?

 

[WaterHole]

The voltage is set at 11.8v. I get just over 12v on the meter - the same as if I connect straight to the battery.

 

[jokiin]

The voltage is set at 11.8v. I get just over 12v on the meter - the same as if I connect straight to the battery.

set the voltage lower (as a test) and see if it then turns on, if it's set to 11.8v you may find that 12v isn't enough to turn it back on, a healthy battery will sit at about 12.4v or higher and when the car is running should be around 14.5v, there may be some sort of regulation going on with the circuit you're using, check at the battery with your meter to see what voltage you get, also check when the car is running

 

[WaterHole]

Ok, although the lowest the PMP will go is 11.8volt. You only have two options 11.8 or 12v.

I'll test the battery when the engine is running, and try the ACC direct to the battery to see if that restarts the unit.

It could be my battery is low, so I'll charge it tonight... to see what happens.

If it's not that, I'm guessing it's faulty.

 

[jokiin]

when a battery goes low the PMP cuts in, once there is no load on the battery the voltage will rise a bit, the threshold needs to be a few points higher than the cutout voltage otherwise the PMP will cycle on and off, if your cutout is 11.8v you'll find 12v is not quite enough to turn it back on, this is normal, 12v while the car is running though is not normal, as I said it might be regulated by the computer in which case you'll need to find another circuit that isn't restricted like this, it may turn out to be a problem if it's a newer BMW though

 

[WaterHole]

Well I've tried a different fuse, and it worked! Strange that, as it gave out the same voltage as the other fuse.

 

[dhavie]

@WaterHole. Which fuse you use? Can you show some photo of the fuse box and the fuse that you tap onto.
Thanks

 

[WaterHole]

Hey, it was fuse for the cigarette lighters.

I used this product: https://www.ebay.co.uk/itm/221696207455 to link the fuse in.

 

[dhavie]

Hey, it was fuse for the cigarette lighters.

I used this product: https://www.ebay.co.uk/itm/221696207455 to link the fuse in.

Thank you mate for the piggyback fuse

 

[Ralph2]

Hey, it was fuse for the cigarette lighters.

I used this product: https://www.ebay.co.uk/itm/221696207455 to link the fuse in.

The fuse for the cigarette lighter seems to have some kinky electronics governing it. My GPS is wired to that circuit.. if I shut the car off.. but only to the "ACC" position my GPS shuts down.. yet.. from a cold position, turning the key to the "ACC" position turns the GPS on. As it turned out (totally by accident) this is OK with me as I ended up using the radio fuse for my ACC connection to my PMP because it was on the right side of the fuse block.