Reversing camera change over relay, permanent live.

[ArtD]

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.

it shouldn't impact the circuit but only camera itself as it is connection from reverse light to camera and not the opposite (unless I'm missing something here). This is in-line relay so not exactly the same as chinese one but similar

 

[roadtripper]

If you put a capacitor across live and ground to filter out the peaks and troughs of a PWM signal that will do it both ways along that circuit, electricity doesn't know which way you want it to flow.

It can be done with a diode as well to ensure the filtering only takes place one side and there is reasonable isolation, I wouldn't fit one without having it open to see how it's been done. Frankly I wouldn't fit one at all I'd fit a canbus adaptor as Dav-Tec mentioned. I appreciate not everyone wants to spend that amount so a relay switching a clean feed as Deaky suggests is a cheaper way of doing something with good isolation. I'd not risk the chance of interfering with the expensive to fix VW electronics further than that myself, but then I may be more sensitive to that given the horrors I've seen customers do to the electronics in the day job...

This isn't a case like the old issues where you could get alternator noise on supposedly clean stable 12v lines where if you did filter it it didn't matter as it was meant to be clean by design - the "noise" here is deliberate part of the vans electronics design.

 

[n10n]

I appreciate not everyone wants to spend that amount so a relay switching a clean feed as Deaky suggests is a cheaper way of doing something with good isolation.

Two more considerations:

• Traditional coil relay will put high voltage inductive spikes back to that precious VW electronics with the PWM pulses. So, a reverse diode across the coil recommended.
• MOSFET relays are usually so fast that they simply follow the PWM - they're not really applicable here, would have to be a coil relay

 

[ArtD]

Two more considerations:

• Traditional coil relay will put high voltage inductive spikes back to that precious VW electronics with the PWM pulses. So, a reverse diode across the coil recommended.
• MOSFET relays are usually so fast that they simply follow the PWM - they're not really applicable here, would have to be a coil relay

thank you both. I think these are fair comments, and I like idea about reverse diode