Reversing camera change over relay, permanent live.

[Clissold7278]

Hi all, after some advice please .
I have wired in my after market reversing camera and all works fine with ignition on and reverse gear selected. But when I start my T6 the screen goes off.

I understand I need a relay which I have ordered, but the relay needs a permanent live. As the relay will be in the back connected to the reverse wire, ground, camera wire would I need to piggy back off a permanent live fuse at the front? Or could I tap into the live wire on rear interior light? Which would be much easier lol.

Thanks

 

[Jim Rey]

why don't you just add an inline fuse holder after you take the feed from the light? In any case the light should be fused anyway.

 

[Clissold7278]

why don't you just add an inline fuse holder after you take the feed from the light? In any case the light should be fused anyway.

I was thinking the same, just not sure after reading other posts if it is a permanent live on the interior light?

It's got to be though hasn't it? Lol

 

[DXX]

If you want the reversing camera to operate when you engage reverse you power it from the reversing light feed.
Not sure why you would want a permanent feed.

 

[Clissold7278]

If you want the reversing camera to operate when you engage reverse you power it from the reversing light feed.
Not sure why you would want a permanent feed.

I'm totally with you and that's what I did. Works when ignition on but not when engine is running. Apparently its common with some vehicles so you need a change over relay to fix it. That's what needs a permanent live Apparently.
I'm no sparky lol, but I'm following advice to fix it. Do you know if the red & black wire in interior light is permanent live?

 

[DXX]

The reversing light obviously works when the engine is running, not sure what the problem is.

 

[Deaky]

If you want the reversing camera to operate when you engage reverse you power it from the reversing light feed.
Not sure why you would want a permanent feed.

Because its a PWM switched +12v from the BCM. Some cameras don’t like it, but it’s good enough for a relay. Use the relay to switch a clean +12v. You may get the same issue using the +ve from the courtesy circuit.

 

[DXX]

I had a WiFi Garmin reversing light and Scenelight maneuvering light running from the reversing light feed and tail light ground with no problems. When I switched tail lights to dual reversing light type the BCM didn’t handle the camera and 3x lights well. It was ‘fixed’ by using a local ground at the D pillar. 2016 van.

 

[Dav-Tec]

You could just buy the appropriate loom the gives you a stable 12v feed when it sees the reverse signal it would be a lot less messing around buddy

 

[Clissold7278]

Because its a PWM switched +12v from the BCM. Some cameras don’t like it, but it’s good enough for a relay. Use the relay to switch a clean +12v. You may get the same issue using the +ve from the courtesy circuit.

Thank you for replying, so it would be better to run a 12v + feed from a fuse in the fuse box at the front?.

Thanks

 

[Deaky]

Thank you for replying, so it would be better to run a 12v + feed from a fuse in the fuse box at the front?.

Thanks

Definitely

 

[Pauly]

Agreed, if you have a camera that doesnt like the twitchy 12v reverse supply a clean 12v supply from the front through a relay is the way to go

 

[Clissold7278]

Definitely

Thanks Deaky really appreciate your help. Silly question, but as there are different amp rated wires out there which would be best for this?

Thanks again

 

[Deaky]

Thanks Deaky really appreciate your help. Silly question, but as there are different amp rated wires out there which would be best for this?

Thanks again

Id have thought 1mm would be fine.

 

[DXX]

Thank you for replying, so it would be better to run a 12v + feed from a fuse in the fuse box at the front?.

Thanks

While you’re doing it I’d pull a spare wire as well in case you want to add something else at a later date. Label both free ends.

 

[ArtD]

Hi Deaky, how about relay filter at camera end (linked to power and ground? Would that override the issue with PWM if 12v is taken only from the reversing light? And potentially it would make live easier with no extra cables going anywhere.

 

[roadtripper]

Where are you getting clean unpulsed 12v from at the rear of the van?

A relay isn't a filter, you put the pulsing 12v PWM signal into a relay driver which causes the relay to switch on a separate unpulsed stable 12v feed to the camera.

 

[Dundee_Kev]

I assume @ArtD is referring to one of these?

They seem to work fine, or at least did on my van

 

[ArtD]

I assume @ArtD is referring to one of these?

They seem to work fine, or at least did on my van

Dundee_Kev, exactly I was refering to such filter as per your post.

 

[roadtripper]

Ah so one of the Lost In Translation Throw Every Search Word In We Can listings - that's not a relay at all...

I'd be wary of using such a solution because the van electrics are doing PWM for a reason. Unless the filtering is done carefully with diodes then you are also going to filter the circuit on the van side in a way it wasn't really designed to be.

I'd always prefer a solution that leaves the stock electrics alone as much as possible.