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Ford Puma: How to reduce DAB interference from rear dashcams

If you have a rear dashcam fitted to your Ford car then they seem prone, particularly on the new Puma’s, to causing interference with the DAB reception. In the case of the Puma, this is because of the location of the DAB antenna.

I had my dashcam fitted by Halfords who did a great job but the interference was terrible, making digital radio pretty much unusable. I took it back a couple of times and, each time, they got it a little better. But I was still unhappy so took things into my own hands and did some experimenting. As a result I’ve got it better still – not perfect, but better.

In my case, I have a Nextbase rear camera. I’m not sure if the issues are specific to Nextbase but Halfords are certainly well aware of dashcams, more generally, causing these issues quite regularly. In fact, the first time I returned after having it fitted, I told a member of staff that I was here about a recently fitted dashcam and he said, “let me guess – DAB reception?”

This isn’t a bash at Halfords – for the money, their fitting is great. Neat and well done. However, they didn’t have the time to spend messing around with it all, as I did, which is why I think they maybe missed the solution here.

Anyway, enough chat, let’s look at how I now have it and break things down from that. Here’s the rear camera with the boot open…

Yes, I know the car needs a wash.

If you see where the cable is going into, that’s a plastic panel which can simply be pulled off. When you do that you get this…

You can see a lot of cabling there but also two radio reception modules. Let’s zoom in on them and spin them around…

The one on the left is marked for AM/FM and DAB. The one on the right, according to the model details marked on it, is an amplifier of some kind. On the label it does say “FM”, suggesting this purely affects FM reception, but I can’t confirm that.

On the Puma, radio reception is not from the aerial on the roof but is via number of thick metal strips that run down the rear windscreen (in preference to those that run horizontally, which is the rear demist). If you look at the bigger picture above you’ll see some thin black and blue cables running from the top of the window into these modules.

However, it’s the much thicker black cables that we need to be concerned about.

When I took my car back to Halfords one of the things they changed was, instead of the camera cable coming in from the left, they moved it to the right, which seems to have been the right decision. However, they then taped it around one the thick cables. What I found was that moving the camera cable away from all of these improves the signal, not just those on the left hand side. And that needs to be your aim.

I also experimented with tucking the cable behind the metal ridge where the bodywork meets the windscreen…

But, as soon as I did that – INTERFERENCE! I suspect, because that’s quite a tight fit, that pushing the camera cable into that essentially turned the bodywork into a giant antenna for the camera signal. So, don’t do that. However, it does make me wonder just how leaky that camera cable is, signal-wise, and whether this is an issue really for Nextbase cameras.

My solution

So, what did I do? It was quite simple in the end. I got inspiration from something that Ford had done already. If you look at the middle of the wiring you’ll see this…

They’ve wrapped velcro around their cable and that white rectangle is the opposite piece, which it sticks to. So, using the same technique I moved my cable up out of the way on the right-hand side…

How did I test all this? Sat on my drive, I found the worst DAB station which I should otherwise have got – it had a signal but you could hear distinct drop-outs. I closed the boot, but with the plastic panel removed, got into the back of the car and simply moved cables around, listening for drop-outs or otherwise.

The final thing is to fit the panel with the cable coming out in the right place – too far to the left and it will be close to that loop of black/white velcro’d cable in the centre.

And has it worked? Stations that were regularly dropping out are now solid. Without any kind of way of seeing exact DAB signal strengths in the car (Ford – please add this!) I have no idea how much this has solved it, but it certainly seems a lot, lot better.

Ferrite Beads/Chokes

Some people talk about using ferrite chokes to try and suppress the interference. I’ve seen some people find that these have helped but, equally, many who have found them not to have.

One of the issues here is quality of these – turning to some cheap product off Amazon may not be the best thing here and, indeed, some that I had seemed to just cause worse issues. The only one I have in use is on the back of the camera…

This was one fitted by Halfords (and moved by me), and may be more suitable for the interference range needing to be suppressed. I don’t know.

Certainly, I had no joy from any that I had.

Talk to me!

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