GARMIN rear dashcam install

[simonds3135]

Has anyone on here managed to fit a GARMIN dashcam in the rear of their Octavia Mk3 Estate? I'm guessing no, because it's absolutely flipping impossible! I have seen lots of other dashcam threads on here where people have fitted rear dashcams, but none that mention GARMIN cameras. The only reason the GARMIN part is important is the parking mode (hardwire) cable they use. The cable is down as being 4m long on the specifications, which when I did a quick flash down the side of the car with a tape measure from the fusebox to the centre of the rear window (and added a bit for good measure), would have been about right. But little did I know, that 4m would be the overall length of the cable, not just the USB part coming out of the 'control box' like I thought it would be. The USB part of the cable coming from the box is actually only 3m long, then there is a 1m section the other side going to the fusebox etc. GARMIN obviously created this cable at a time when rear dashcams weren't a thing as it's just far too short. The overall length is okay, but this would put the 'control box' (which is part way down the cable) right smack at the top of the A pillar, where a) there is no room and b) there are air bags. I'm guessing that because of this, I simply cannot have a GARMIN dashcam in the rear of my car and it's just tough luck, but I wanted to see if anyone else had any genius ideas or used a different cable or extended the GARMIN cable or whatever. I only went with a GARMIN camera (DashCam Mini 2) for the rear because I already had a GARMIN DashCam 56 in the front, so to link them up, the rear one would also need to be a GARMIN. 

 

Any help or advice on this would be hugely appreciated! 🙂

[ApertureS]

Do they not offer some kind of extension?

 

have you got a photo of the dash cam in question and it’s wires?

[TheClient]

10 hours ago, simonds3135 said:

Has anyone on here managed to fit a GARMIN dashcam in the rear of their Octavia Mk3 Estate? I'm guessing no, because it's absolutely flipping impossible! I have seen lots of other dashcam threads on here where people have fitted rear dashcams, but none that mention GARMIN cameras. The only reason the GARMIN part is important is the parking mode (hardwire) cable they use. The cable is down as being 4m long on the specifications, which when I did a quick flash down the side of the car with a tape measure from the fusebox to the centre of the rear window (and added a bit for good measure), would have been about right. But little did I know, that 4m would be the overall length of the cable, not just the USB part coming out of the 'control box' like I thought it would be. The USB part of the cable coming from the box is actually only 3m long, then there is a 1m section the other side going to the fusebox etc. GARMIN obviously created this cable at a time when rear dashcams weren't a thing as it's just far too short. The overall length is okay, but this would put the 'control box' (which is part way down the cable) right smack at the top of the A pillar, where a) there is no room and b) there are air bags. I'm guessing that because of this, I simply cannot have a GARMIN dashcam in the rear of my car and it's just tough luck, but I wanted to see if anyone else had any genius ideas or used a different cable or extended the GARMIN cable or whatever. I only went with a GARMIN camera (DashCam Mini 2) for the rear because I already had a GARMIN DashCam 56 in the front, so to link them up, the rear one would also need to be a GARMIN. 

 

Any help or advice on this would be hugely appreciated! 🙂

I think your easiest solution by far is to extend the power cables for the control box (which you have to do anyway, to some degree, as garmin don't provide fuse connections or piggy backs).

 

Then run the cable along the door sills area. At some position going up to rooflining if required significantly further back in car. 

 

You'll have to hide that annoying control box say under the rear seat along the way, maybe cut out some underlay, and continue the factory cable from there untouched.

 

Looking at this helpful tear down video you could resolder the USB side on the board end and leave the mini USB with the embedded resistor untouched i.e. just extend it from board.

 

But you'll have to open the control box loosing warranty, you'll have to solder direct on the board and you'll have to do something with the seal bung,  see if it could be removed from the original cable and repositioned onto extended wire entry. Seems much more of a faff.

 

 

 

 

 

 

 

 

 

Edited 6 November, 2023 by TheClient

[simonds3135]

4 hours ago, TheClient said:

I think your easiest solution by far is to extend the power cables for the control box (which you have to do anyway, to some degree, as garmin don't provide fuse connections or piggy backs).

 

Then run the cable along the door sills area. At some position going up to rooflining if required significantly further back in car. 

 

You'll have to hide that annoying control box say under the rear seat along the way, maybe cut out some underlay, and continue the factory cable from there untouched.

 

Looking at this helpful tear down video you could resolder the USB side on the board end and leave the mini USB with the embedded resistor untouched i.e. just extend it from board.

 

But you'll have to open the control box loosing warranty, you'll have to solder direct on the board and you'll have to do something with the seal bung,  see if it could be removed from the original cable and repositioned onto extended wire entry. Seems much more of a faff.

 

 

 

 

 

 

 

 

 

 

Hi TheClient, thanks for your detailed response. Well I did think of extending the power side of the 'box' and leaving the USB side as it is from factory, but to get the box out of the way, I'd have to extend the power side to nearly 4m just so the box could be in the rear of the car. I'm guessing that's safe and it would still actually function correctly? Seems very silly, nothing is ever simple! 😄

[HappySam]

Surely there must be a perm live and switched live in the rear of the car you can piggy back off?

 

I know the accessory socket in my boot is permanently live. Does the rear wiper have a switched live?

[TheClient]

3 hours ago, simonds3135 said:

 

Hi TheClient, thanks for your detailed response. Well I did think of extending the power side of the 'box' and leaving the USB side as it is from factory, but to get the box out of the way, I'd have to extend the power side to nearly 4m just so the box could be in the rear of the car. I'm guessing that's safe and it would still actually function correctly? Seems very silly, nothing is ever simple! 😄

Yes. You can extend as far as you want as long as you use required cable size for voltage drop.

 

Surely there would be someway to stow that control box along the way to rear of car? It looks quite small? I reckon if you got all cill trim off you would find somewhere. .. 

 

Per @HappySamsee if anyone comes up with anything else in response -  in rear of car -  to use for the SL. As that would save a lot of pulling trim apart as well.  

[simonds3135]

4 hours ago, HappySam said:

Surely there must be a perm live and switched live in the rear of the car you can piggy back off?

 

I know the accessory socket in my boot is permanently live. Does the rear wiper have a switched live?

 

Well yes, I was thinking that but I'm not sure where to start really. It's a lot easier to test a fusebox for perm live and acc live etc than a bunch of wires going everywhere in the boot of the car 😕 Plus isn't it much safer to start in the fusebox? You'd have to add in some sort of fuse if you managed to tap into the rear wiring somewhere wouldn't you? 🤔

[simonds3135]

4 hours ago, TheClient said:

Yes. You can extend as far as you want as long as you use required cable size for voltage drop.

 

Surely there would be someway to stow that control box along the way to rear of car? It looks quite small? I reckon if you got all cill trim off you would find somewhere. .. 

 

Per @HappySamsee if anyone comes up with anything else in response -  in rear of car -  to use for the SL. As that would save a lot of pulling trim apart as well.  

 

How would I work out the required cable size for the voltage drop? If there was a voltage drop, would it not work correctly?

 

The control box is bulkier than it seems, especially when you're trying to hide it in some roof lining or behind some trim! It's 50mm x 43mm x 20mm.

[simonds3135]

5 hours ago, TheClient said:

Yes. You can extend as far as you want as long as you use required cable size for voltage drop.

 

I'm thinking something like this would do the trick?...

 

49.2ft 18AWG 3×0.75mm² Electrical Wire 3 Core, 18 Gauge 3 Conductor Black PVC Case Stranded Low Voltage Cable High Temperature Resistant,Tinned Copper Automotive Wires, Flexible Extension Power Cord https://amzn.eu/d/3OzAdmb

[TheClient]

14 hours ago, simonds3135 said:

 

I'm thinking something like this would do the trick?...

 

49.2ft 18AWG 3×0.75mm² Electrical Wire 3 Core, 18 Gauge 3 Conductor Black PVC Case Stranded Low Voltage Cable High Temperature Resistant,Tinned Copper Automotive Wires, Flexible Extension Power Cord https://amzn.eu/d/3OzAdmb

What is acceptable comes from v=ir.  And you need the length (double for return cct), cable resistance (varies with cross section) and current draw.

 

So, say 4amps, (probably over kill) 8 metres, acceptable voltage drop 2 or 3%. Tables I see with cross sections,  suggest 1.3mm2 to 1.5mm2 at least.

 

But then again, the current draw of that camera won't be 4 Amps so in all likelihood you may well get away with 0.75mm2. 

 

If you Google for some Automotive cable specs and voltage drop calculator you'll see what I mean.. as long as the cable is fused appropriately for cable capacity,  too small a cable doesn't create any risk but the item may not function at too low voltage.  

[simonds3135]

4 hours ago, TheClient said:

What is acceptable comes from v=ir.  And you need the length (double for return cct), cable resistance (varies with cross section) and current draw.

 

So, say 4amps, (probably over kill) 8 metres, acceptable voltage drop 2 or 3%. Tables I see with cross sections,  suggest 1.3mm2 to 1.5mm2 at least.

 

But then again, the current draw of that camera won't be 4 Amps so in all likelihood you may well get away with 0.75mm2. 

 

If you Google for some Automotive cable specs and voltage drop calculator you'll see what I mean.. as long as the cable is fused appropriately for cable capacity,  too small a cable doesn't create any risk but the item may not function at too low voltage.  

 

That's brilliant, thank you so much for your help. I'm guessing it's better to have a cable that's slightly too thick rather than too thin? 

[TheClient]

10 minutes ago, simonds3135 said:

 

That's brilliant, thank you so much for your help. I'm guessing it's better to have a cable that's slightly too thick rather than too thin? 

It is the better way. But the downside is it makes hiding it and cable flexibility worse. 

[TheClient]

1 minute ago, TheClient said:

It is the better way. But the downside is it makes hiding it and cable flexibility worse. 

The other thing is you may be able to use 2 core and only earth at the site of the control box to a good body earth point. 

[ApertureS]

18 hours ago, TheClient said:

What is acceptable comes from v=ir.  And you need the length (double for return cct), cable resistance (varies with cross section) and current draw.

 

So, say 4amps, (probably over kill) 8 metres, acceptable voltage drop 2 or 3%. Tables I see with cross sections,  suggest 1.3mm2 to 1.5mm2 at least.

 

But then again, the current draw of that camera won't be 4 Amps so in all likelihood you may well get away with 0.75mm2. 

 

If you Google for some Automotive cable specs and voltage drop calculator you'll see what I mean.. as long as the cable is fused appropriately for cable capacity,  too small a cable doesn't create any risk but the item may not function at too low voltage.  

That is a bit overkill for what’s required.

 

OE wiring uses 0.5mm wire for runs up to and sometimes over 10 meters long at 10amp,

a 0.5mm cable is more than sufficient for an amp or two from a dash cam.

 

voltage drop in a day to day car is negligible and really doesn’t come into it much as the cable lengths are so short compared to housing or national power lines.

[TheClient]

31 minutes ago, ApertureS said:

That is a bit overkill for what’s required.

 

OE wiring uses 0.5mm wire for runs up to and sometimes over 10 meters long at 10amp,

a 0.5mm cable is more than sufficient for an amp or two from a dash cam.

 

voltage drop in a day to day car is negligible and really doesn’t come into it much as the cable lengths are so short compared to housing or national power lines.

True. In reality, thinking about a likely current draw, a dash cam is probably 1amp or possibly less when fully active. I did say it would be overstated! 

[J.R.]

4 hours ago, ApertureS said:

That is a bit overkill for what’s required.

 

OE wiring uses 0.5mm wire for runs up to and sometimes over 10 meters long at 10amp,

a 0.5mm cable is more than sufficient for an amp or two from a dash cam.

 

voltage drop in a day to day car is negligible and really doesn’t come into it much as the cable lengths are so short compared to housing or national power lines.

 

Whilst I agree with all that you say voltage drop is more significant the lower the supply voltage, cable sizes for 12v systems are far larger for a given length and volt drop than they would be for a 240vac system.

 

Unless you are dealing with starter motor solenoid, headlights, air horn compressor, accessory sockets etc then 0.5mm csa is the order of the day.