Unswitched port in fuse box

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Can I ask how you know that this connector is unswitched? I'm not doubting what you say, but it would be interesting to know where the info came from?

I'm interested because it could be a convenient point to connect up a battery monitor, to display the voltage on the 12V battery.

If by "parking monitor" you mean a cam that is permanently powered to start recording if any impacts are sensed, I'd be cautious - the 12V battery isn't very high-capacity and relatively expensive to replace, so it might be wise to avoid any permanent loads on it?
 
The i3 might have 3 categories of fuse connectors: switched, unswitched with time-out, unswitched without time-out. We know that some accessories don't turn off immediately when exiting drive ready state but turn off after ~15 minutes. The only 12 V loads that I can think of that always remain on are the hazard warning flashers and the roadside parking lights.
 
Hi Art - do you know of a good online reference for the fuse panel allocations?

One problem is that the only sources I've found so far are like the one at:

https://fuseandrelay.com/bmw/i3.html

It's better than nothing, but the descriptions start at 39 and end at 84 for some unknown reason, and some of the descriptions are (as others have commented here) a bit hit and miss - e.g. "Stove logic"!!
 
mojo said:
Hi Art - do you know of a good online reference for the fuse panel allocations?
Click to expand...
Unfortunately, not. I couldn't find anything in BMW's i3 Technical Training Manuals which is surprising. There's probably a lot more information in BMW's Technical Information System, but an expensive subscription is required.

Maybe use a voltmeter to measure the voltage of each fuse after the 12 V system has automatically shut off.
 
mojo said:
Can I ask how you know that this connector is unswitched? I'm not doubting what you say, but it would be interesting to know where the info came from?

I'm interested because it could be a convenient point to connect up a battery monitor, to display the voltage on the 12V battery.

If by "parking monitor" you mean a cam that is permanently powered to start recording if any impacts are sensed, I'd be cautious - the 12V battery isn't very high-capacity and relatively expensive to replace, so it might be wise to avoid any permanent loads on it?
Click to expand...

Yes. I found the info from this forum.

https://www.mybmwi3.com/forum/viewtopic.php?t=4324

And yes. Thats what i meant. I need constant 12v.
 
That's an odd type of connector - it looks rather like a test point. I wonder if there is some type of BMW diagnostic equipment that plugs in there? I'll have a look on my car when I have the time, and see if there is a link from that connector to any of the fuse slots.

I did consider whether to get a dashcam with parking mode, but (in the UK at least) it doesn't seem to be a very useful function, because generally it won't capture the information that you really need to be able to use the footage as evidence.

In the end I came to the conclusion that fuse 65 or 127 should be Ok for my purposes - the power stays on long enough to capture any road rage incidents, but not long enough to risk running down the 12V battery while (for example) you're away on holiday.**

Having said that, I see that it's fairly easy to get "dashcam hardwire" kits that include a voltage monitor that will turn off the camera supply when the battery drops to (say) 11.6V, and that's probably enough to stop it from dropping too low for the car to power up.

[**Edit: Just noticed that the i3 has a 20Ah battery - this is a quarter the capacity of the battery fitted to my other car. Worth bearing in mind when considering how long a dashcam with Parking Mode will run before flattening the battery!]
 
mojo said:
That's an odd type of connector - it looks rather like a test point. I wonder if there is some type of BMW diagnostic equipment that plugs in there? I'll have a look on my car when I have the time, and see if there is a link from that connector to any of the fuse slots.

I did consider whether to get a dashcam with parking mode, but (in the UK at least) it doesn't seem to be a very useful function, because generally it won't capture the information that you really need to be able to use the footage as evidence.

In the end I came to the conclusion that fuse 65 or 127 should be Ok for my purposes - the power stays on long enough to capture any road rage incidents, but not long enough to risk running down the 12V battery while (for example) you're away on holiday.**

Having said that, I see that it's fairly easy to get "dashcam hardwire" kits that include a voltage monitor that will turn off the camera supply when the battery drops to (say) 11.6V, and that's probably enough to stop it from dropping too low for the car to power up.

[**Edit: Just noticed that the i3 has a 20Ah battery - this is a quarter the capacity of the battery fitted to my other car. Worth bearing in mind when considering how long a dashcam with Parking Mode will run before flattening the battery!]
Click to expand...


So you think its not really feasible to have parking mode hardwired? Theres also an option to purchase a small battery, maybe i should start researching that instead
 
It's feasible - but the two questions of most importance are whether it will deplete the battery too quickly, and whether it has any value anyway.

I don't know where you are, but in the UK the problem is that the most you are ever likely to see is a vehicle hitting yours, and if you are lucky you may see the registration plate. Even with the latter, the police reaction will be "we cannot prosecute a car". Your footage will almost never enable you to identify the ~driver~ and so it is, in effect, useless.

How long a 20Ah battery will last while the vehicle is parked depends on the power consumption of the camera. Unfortunately most manufacturers don't state the consumption, so it's an unknown factor to me...
 
I really hate it when people reply with a response that doesn't answer the question asked, but I'm going to do just that.

Everyone who says that the i3 battery is very small and basically just for running the start-up electronics is correct. You don't want to driain the i3 12v battery. That being said, I have a small LiFePO4 battery in the car -- these are very compact and light for the amp hours supplied.

When the car is being driven, the load (in your case the alarm / camera thingie) and the LiFePO4 battery gets charged. When the car turns off, the load is switched to the LiFePO4 battery. https://www.westmountainradio.com/product_info.php?products_id=epic-pwrgate
 

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