Towbar Electrics for modern cars

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fastbike

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#324199 11-Mar-2026 16:30

I have bought a new car and want to get a towbar fitted.

How are the electrical connections handled ? My last ancient car just had wires spliced into the loom where the bulbs for taillights and indicators were located. This car had old school bulb lamps - new car has LEDs and it is all controlled via a CAN bus.

So assuming something a bit smarter is involved. I've sent inquiries to two local places and not had a satisfactory reply.

I saw a UK made youtube video where a smart relay was used - with 7 signal wires spliced into the loom and a separate fused 12v wire running from the car battery. Is this what will be fitted here ?

Otautahi Christchurch

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#3469033 11-Mar-2026 17:11

Any of the major towbar fitters will know what your car will need. LED doesn't necessarily mean bus controlled. Our 2019 with LEDs has the connection socket just wired to the loom behind the tail lights.

fastbike

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#3469035 11-Mar-2026 17:23

Bung:

Any of the major towbar fitters will know what your car will need. LED doesn't necessarily mean bus controlled. Our 2019 with LEDs has the connection socket just wired to the loom behind the tail lights.

Did you buy it new, or second hand? NZ New or imported ?

I'm not wanting to cause any warranty issues, and can just see this being one where if there are any electrical problems the factory warranty will have an exclusion.

Otautahi Christchurch

Stu1

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#3469042 11-Mar-2026 17:35

Mine is weird it’s a factory outlander one it runs to the battery and has its own fuse. The local dealer had no idea even though it was installed at their head office. Worked it out from you tube

fastbike

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#3469043 11-Mar-2026 17:40

Stu1:

Mine is weird it’s a factory outlander one it runs to the battery and has its own fuse. The local dealer had no idea even though it was installed at their head office. Worked it out from you tube

That's what I saw on the YT video. There is a box of tricks that only senses the signal from where it clips into the loom. so does not draw any current.The power for the trailer lights is supplied by the 12V connection via a fuse to the battery.

The battery for this new car is mounted in the boot so it should be straightforward to connect it there.

Towbar Express just sent me a generic response with no details. I might try calling a different place.

Otautahi Christchurch

lxsw20

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#3469049 11-Mar-2026 17:49

Have you asked Blackwell / Loadmaster they are one of the better known for 3rd party tow bars in Nz and will likely have the wire kit / conversion box.

fastbike

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#3469051 11-Mar-2026 18:07

lxsw20:

Have you asked Blackwell / Loadmaster they are one of the better known for 3rd party tow bars in Nz and will likely have the wire kit / conversion box.

I didn't have them on my list. I'll call tomorrow

Otautahi Christchurch

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mudguard

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#3469057 11-Mar-2026 18:39

I'd probably check with the dealer too? Oddly my current model Corolla has a two inch hitch receiver. I wasn't expecting that when I got installed. I'm tempted to borrow a friend's six bike vertical rack just for giggles to see what it looks like on a tiny hatch. The electrics on mine are the seven or so plugs in the large rectangle. No idea what it's called.

fastbike

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#3469180 11-Mar-2026 20:59

mudguard:

I'd probably check with the dealer too? Oddly my current model Corolla has a two inch hitch receiver. I wasn't expecting that when I got installed. I'm tempted to borrow a friend's six bike vertical rack just for giggles to see what it looks like on a tiny hatch. The electrics on mine are the seven or so plugs in the large rectangle. No idea what it's called.

It's a Nissan, branded towbar is in excess of $2k, but the real issue is there are none in the country and they are quoting 3 months to supply

Otautahi Christchurch

tweake

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#3469187 11-Mar-2026 21:15

fastbike:

It's a Nissan, branded towbar is in excess of $2k, but the real issue is there are none in the country and they are quoting 3 months to supply

??? sounds like you got the "go away and bother someone else" reply. they typically don't use overseas tow bars. they are normally locally made. "best bars" was a common brand for nissan imho.

fastbike

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#3469217 12-Mar-2026 03:18

I've had a poke around the web to see how this is handled correctly.

The Nissan kit uses an ecu from Erich Jaeger. There's also a similar kit from ECS in the UK.

Both avoid cutting into the loom or clipping any wires into it, thus avoiding any warranty issues. Both use an existing connector in the car's CAN bus wiring in a cavity behind the boot liner, with a piggy back plug that connects the ecu to the existing CAN bus and 12v supply.

I'll have a talk to a technical person at an installer tomorrow, otherwise I'll just get the mechanical bit done and DIY the electrics with a kit.

Otautahi Christchurch

fastbike

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#3469218 12-Mar-2026 03:20

tweake:

??? sounds like you got the "go away and bother someone else" reply. they typically don't use overseas tow bars. they are normally locally made. "best bars" was a common brand for nissan imho.

I seem to be getting that feeling. I bought the car from a dealer in Wellington as Nissan Chch were unable to supply as it was a runout sale.

I just reviewed the email from the local parts guy - it was $2.5k plus fitting plus wiring plus GST !!!

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#3469222 12-Mar-2026 07:07

You would find the Nissan dealer would want to fit genuine and then send it off to a tow bar specialist to fit it, hence why they have batted you off to go sort this yourself / save some cash without saying that explicitly to you.

id recommend you just turn up to the place you already called and do checkout blackwells (loadmaster).

they have been both fitting tow bars for a very long time and probably fit them for all the reputable dealers.

turning up and asking questions is the best…..automotive industry ain’t very good with electronic communication……

Bung

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#3469232 12-Mar-2026 08:17

fastbike:

It's a Nissan, branded towbar is in excess of $2k, but the real issue is there are none in the country and they are quoting 3 months to supply

Why not just state the model?

Even if the bar is made locally it would probably be in batches rather than individually. Other installers could be waiting as well.

There are some can bus kits for Nissans advertised in NZ in $400 - $450 range.

trig42

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#3469236 12-Mar-2026 08:42

I know when we got our Kia, I asked about them fitting a tow bar. They told me they just send them to Best Bars and whack a KIA sticker on it.

I got mine done at North Shore Towbars (was walking distance to work). No issues.

Stu1

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#3469530 12-Mar-2026 17:17

fastbike:

tweake:

??? sounds like you got the "go away and bother someone else" reply. they typically don't use overseas tow bars. they are normally locally made. "best bars" was a common brand for nissan imho.

I seem to be getting that feeling. I bought the car from a dealer in Wellington as Nissan Chch were unable to supply as it was a runout sale.

I just reviewed the email from the local parts guy - it was $2.5k plus fitting plus wiring plus GST !!!

yup not cheap , we ended up buying an ex head office outlander as it already had the tow bar fitted, buying the new car was 2.k for tow bar and another 1000 for ORC and car mats. Absolutely crazy cost to get one fitted

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