I'm being lazy - need to know which fuse to use..

crabu2

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Sorry is this is the wrong forum, but I figured it needed to go here or the general dash cam forum. I went with this as you can see.

Ok.. I've got 3 vehicles I need to install hardwire kits on..

'07 Toyota Camry
'15 Ram 3500 (Cummins)
'17 BMW 230xi

I'm not sure which fuse to tap in to. In the past, I would have just looked for a fuse that had power, when the car is just parked, but I keep seeing posts where people are tapping a fuse that's on ACC. I don't get it.. why?

If one wants their dash cam to work in parking mode, wouldn't you need to find a fuse that has power all the time?

My final question is.. if I want to use Parking mode, can anyone tell me which fuse I need to tap on these vehicles?

Thanks!
 
I believe @niko has posted some good info and tutorials about fuses and taps and there are a number of threads on the subject here on DCT. He's always very knowledgeable about such things and happy to help. I think @Street Guardian USA may be able to offer some guidance or resources to look at as well. Perhaps @jokiin also.
 
which cameras?


I'm still not sure yet. I just figured I'd installed something with a USB mini connector. It seems to be the most common on dash cams. If I need a micro, I'll just add a adapter.

My biggest thing is which fuse I should tap so parking mode works.
 
I'm still not sure yet. I just figured I'd installed something with a USB mini connector. It seems to be the most common on dash cams. If I need a micro, I'll just add a adapter.

My biggest thing is which fuse I should tap so parking mode works.

Basically, you can choose almost any available circuit that remains hot after you turn off your ignition and that has enough current to adequately handle both its original purpose along with whatever current your dash cam draws. With certain cars today you may have to be careful with the onboard computer's monitoring of the circuit you want to tap so that you don't trigger an unwanted issue. This "may" apply more to your BMW than the other two.
 
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Basically, you can choose almost any available circuit that remains hot after you turn off your ignition and that has enough current to adequately handle both its original purpose along with whatever current your dash cam draws. With certain cars today you may have to be careful with the onboard computer's monitoring of the circuit you want to tap so that you don't trigger an unwanted issue. This "may" apply more to your BMW than the other two.

That's why I was asking. It seems the the dang ECM likes to shut down stuff after 15 mins, even in the '07 Camry.

I would have thought someone here could have said my Toyota is hardwired to radio, my BMW is hardwired to keyless entry, my Ram had to be hardwired to the battery.. You know answers like that.

BTW, it's a royal pain trying to find a always on circuit because I need to get something to make the cars think the doors are close. With them open, stuff is dinging and blinking and what not.
 
I'm certainly no expert in hard wiring dash cams having never done it. I'm sure there are others here who can give you more of the practical advice you are seeking though.
 
I'm still not sure yet. I just figured I'd installed something with a USB mini connector. It seems to be the most common on dash cams. If I need a micro, I'll just add a adapter.

My biggest thing is which fuse I should tap so parking mode works.

choose your cameras first, some will be ok with those power supplies, others won't
 
My advice: use fuses 10A/15A/20A. Don't use any safety ones like airbags, alarm. I like to use accessory slots, 12V socket, air con, rear wiper or the head unit. Please ask if you have any other questions. I'm a technician that has been trained how to install through hardwire front dash cams. A similar principle applies to hardwiring sat navs and things like phone chargers. Although these use cigar socket to molex plugs. All the best.

Cam
 
Welcome to DCT @CamWake24
Your advice is good and is generally followed; it's been long spoken of here. But with many of today's cars and their computer-controlled power schemes you sometimes cannot find a non-safety-related fuse which functions as you need it to, and sometimes no fuses do that :( What was once simple and easy for the average person to do themselves can now end up being a nightmare for even the Pro's. It's still best done this way if possible ;)

Phil
 
When all else fails go to the service counter at your dealership and ask what fuse you can use.
 
When all else fails go to the service counter at your dealership and ask what fuse you can use.


Now that's funny.. Those guys will be like ... "Unless you pay us to install it, it will void your warranty" or "it can't be done without possibly causing major problems"

Hate to say it, but most dealer service guys, especially the service writers have no idea how to fix anything. It seems most are dealer mechanics are now just parts changers. When the OBD2 reader shows a code, they look at the service manual to see what parts might need changing. without a set code, most are lost.
 
When all else fails go to the service counter at your dealership and ask what fuse you can use.

They won't tell you, partly because they don't know and partly because their job is keep you separated from their Technicians who might know so that the dealer doesn't incur any liability if you do something that causes problems. That guy at the Service counter is essentially just an appointment-setting clerk :( You usually find technical advice more easily gotten from the Parts counter where at least they have some real familiarity with the product, and often one of the Technicians will be on the spot getting parts for their work so you might get the answer right away instead of waiting ;)

Phil
 
Use a multimeter. Set it to DC voltage and the correct significant figures, then connect it to each individual fuse to test for power when the car ignition is on but not started.
 
Use a multimeter. Set it to DC voltage and the correct significant figures, then connect it to each individual fuse to test for power when the car ignition is on but not started.

I'm being lazy... I was hoping someone else would have already done the leg work and could say fuse x is always hot or fuse 4 is ACC.
 
The radio fuse probably is switched. However, many car radios have 2 power supplies. One for always on power to retain preset stations and the time. The radio has another fuse that is switched on and off with the ignition so the radio will not keep playing after the car shuts off.
 
The dome/interior lights are usually ON always.
An accessory would be something like the wipers that only run when the ignition is on.
HOWEVER, you will need to check with a multimeter whether what you think is an accessory fuse really does turn off with ignition off or after some minutes.

Parking mode can be enabled in different ways, depending on camera model.
- If parking mode is detected by lack of car movement, you'll need an always ON fuse (interior lights, usually).
- If your camera uses a 3 wire hardwire kit, parking mode is detected by ignition off. Power is supplied by the always ON connection. The yellow accessory cable is simply for the camera to detect lack of voltage there to trigger parking mode.

As much as we'd love lazy answers, it'd be a great coincidence to get the easy answers for your 3 cars! Google will at least get you the fuse box layouts.

By the way, if you did get the answers you needed, please share them for other readers here.
 
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this is off topic but thought I’d throw it in, a few yeas back (2004) we had bought a new car, not just new to us but a new car, after around 6 or 7 months we noticed overtime we went to turn the key we would hear a couple of buzzer sounds, a bit like those you hear if you’ve opened the car door and still have the key in the ignition but our sound was much softer

we went through the manual and there was no mention of this in it so we carried on, when one day my wife phones me as she can’t get the car to start, I drive home and try to start the car, turning the key was like turning the key on a car with a dead battery, except everything else on the car worked except for starting

I phoned the MG Rover dealer we bought our car from (our car was the Rover MG TF) explaining our symptoms I asked what might the issue be, they said unless we took the car to them there was no way of knowing what it could be,

well I told him if I could drive the car to him I wouldn’t have an issue as I can’t start the car, I asked I’m if they had a tow truck to pick up the car but was told to organise on myself

I went on the internet and did some searching and sure enough in under 10 minutes the issue I was having popped up, the fob key needed a new CR3032 battery in it, we had a box of them. replaced the battery and off we went,

our fob key was only to arm or disarm the alarm, it didn’t open the doors, so as locking the car also armed the alarm we never used the fob to set the alarm, but the fob key had to be wishing a few CM’s of the key when starting the car of the car wouldn’t start and as the battery died the car wouldn’t start, I am sure the guy at the dealers could of saved me no end of time but if I was able to take it to them I’m sure I would of walked out with a few hundred pounds less in my pocket all for a £1 fob battery

sorry for being off topic
 
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