2017 CX5 - which trailer wiring kit: Curt or Tekonsha
- Thread starter Lbear
- Start date
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- 2017 CX-5 GT AWD
The mazda kit is out, i ordered it and installed it; from mazdaparts.org. The tekomsha requires running wires to battery. The mazda kit taps into power block.
https://www.mazdaparts.org/mazdaq-cx5-trailer-hitch-wiring-harness-kit.html
https://www.mazdaparts.org/mazdaq-cx5-trailer-hitch-wiring-harness-kit.html
The one problem/issue I see with the Mazda unit is that it require TAPPING into power lines. The other kits I mentioned are plug & play, not tapping into existing power wires. Tapping into existing wires means you are cutting into them, which always leaves a potential problem later on.
Yes, the other kits require running an individual power cable from the battery but ask any truck/trailer towing mechanic and that is the best way to run power to the trailer. The main reason is that if there is a short on the trailer wiring, it doesn't blow out your cars wiring since it is on its own power source. The Mazda kit would blow out your vehicles brake lights and fuse. Not a good setup.
Not sure why Mazda went that route this time. The 2016 and older Mazda OEM trailer wiring kits tapped into battery power at the front.
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- 2017 CX-5 GT AWD
You misunderstand the mazda wiring harness.
All require tapping into Brake, signal, running lights - and have a module that sends signals to the trailer. The mazda kit lets you tap into the power at the rear of the vehicle instead of running wires all the way to the front. Other then that, the kits are the same. A signal/power module that taps into the lights on the car, and when they signal, the power module sends power to the appropriate trailer light. Maybe the after market kits use a plug instead of a tap - but i have to think Mazda had a reason for doing the things the way they did.
The mazda kit has the advantage of using a system fuse and not having to connect direct to the battery. Cleaner in my opinion. The aftermarket kit will have its own fuse. You also have to run wires to the front and through the firewall, hiding that wire and avoiding any sharp areas it could short. Not impossible, but even more interior disassembly then needed for the mazda kit.
When it comes to wiring, I will go OEM everytime over aftermarket. Someone here posted about an issue with one of the aftermarket kits causing problems, but the dealer installed it, so the dealer had to fix it.
Very happy with my choice, and if I have a problem, there are only 2 of us pointing fingers, not a triangle.
The aftermarket kits use a plug. The OEM plug just plugs into the back of the trailer plugs. So no splicing/tapping like the Mazda kit.
Most electrical people don't like taps since it is not a clean connection. In other words, it's an afterthought.
Mazda is not in the trailer towing business. They are a car manufacturer so when it comes to towing, it's not Mazda's specialty. Curt and DrawTite are in the car towing business, that's what they do and specialize in.
Don't get me wrong, I am not knocking your decision, as I am still undecided. I am just not 100% confident that Mazda has the better trailer harness. Cutting/tapping into factory wires is something that can cause problems down the road since it's not a clean connection.
Remember, nowhere else in the entire CX5 is there a tap connection, nowhere. The factory will use butt splice connections but NEVER a tap connection. Splice tap connections are not secure and not a professional electrical connection, that is why Mazda doesn't use them anywhere else.
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- 2017 CX-5 GT AWD
i get what you are saying. but the power connection is not a tap - it is a wire inserted into the factor plug, locked in place and then part of the harness. Yes, the sensing wires are tapped, but as they are not truly carrying current to the trailer I don't mind.
I have installed other Mazda kits that did use inline plugs. And since Mazda didn't use taps everywhere in the trailer wiring kit, i still think they had a reason to use those taps instead of using an inline plug. But even if that is not the case, I still believe Mazda knows the electrical properties of their vehicle better then a hitch company
The power source into the factory plug is fine but again, the trailer wiring can short out the Mazda's wiring because the power is coming from the factory plug instead of directly from the battery. If there is a short on the trailer (possible and quite common), then it will screw with your Mazda electrical and lighting. Per eTrailer:
The whole idea of routing the wire directly to your battery is to bypass the wiring on your vehicle anyways. This means that if something were to happen to the wiring on your trailer the wiring on your CX-5 would remain unaffected.
My biggest issue with the Mazda setup is that the splice taps. The ONLY reason WHY Mazda would use taps is because of ease of wiring and expense. Plug and play is more $.
Like I said before. I would consider the Mazda setup but I am hesitant due to the splicing taps being #1 (you are literally cutting into factory wiring) and then tapping into the Mazda power source being #2. When the trailer wiring shorts out, it will take out your cars lights with it, leaving you with no tailights.
The whole idea of routing the wire directly to your battery is to bypass the wiring on your vehicle anyways. This means that if something were to happen to the wiring on your trailer the wiring on your CX-5 would remain unaffected.
My biggest issue with the Mazda setup is that the splice taps. The ONLY reason WHY Mazda would use taps is because of ease of wiring and expense. Plug and play is more $.
Like I said before. I would consider the Mazda setup but I am hesitant due to the splicing taps being #1 (you are literally cutting into factory wiring) and then tapping into the Mazda power source being #2. When the trailer wiring shorts out, it will take out your cars lights with it, leaving you with no tailights.
Also, forgot to mention, just 2 months ago the OEM Mazda trailer lighting kit was recalled due to issues. So apparently Mazda didn't have the trailer lighting figured out. There are forum posts about this. Supposedly it was recalled back in December 2017.
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Not sure why the Mazda US and Canada harnesses are different. I ordered and installed the OEM harness here in Canada and it was plug and play for the tail light signals with a "T" harness and the pin to insert the wire in the rear harness for power. There was no tapping or splicing of any wires at all.
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- 2017 CX-5 GT AWD
Sorry but i disagree. If your trailer wiring shorts out, it could take the mazda trailer module out, and maybe the fuse that powers the trailer module. Neither are part of the lighting circuit. The manual even says that if the converter is overloaded or shorted it will shutdown to protect the lights. I guess the converter itself could fail and take out the fusebox fuse, but don't think it is the light fuse - i haven't checked.
The etrailer harness still plugs into the same place as the splices are in order to detect signals to the lights. If the etrailer harness converter fails it can blow the fuse at the battery. So either solution has a fuse - mazda in the fuse block, etrailer under the hood. Both have converter modules that tap into the car lights to sense the signal.
I have had no problems with quality taps installed the proper way. I can see one reason Mazda went this way was to avoid routing the harness to both rear tail lights - all work is done on one side. They could have had a plug and play connector for the left tail-light, but to get turn signal for right side still would need a tap - unless you route a wire and plug to the right side. So they probably did save money by just having 4 wires tapped. As lots of things on the mazda use the CAN bus for signalling and power is supplied separately, the wires may be tapped into the signaling bus, and they thought it was a low risk solution.
I was just sharing my experience. I prefer OEM wiring as i trust it more, even if it uses taps for some things. Installation was easy and quick, I didn't need to rig a tap at the battery, and all trailer wires worked as soon as i was done.
As for the recall, i thought it had to do with routing of wires near the muffler, but i could be wrong.
We will have to agree to disagree. The ONLY reason why Mazda went the route it did with its trailer wiring harness is for the sake of cost savings $$ and mechanic labor savings $$. It's much cheaper and faster to use splice tap connections than it is to use butt end connections or plug and play connections.
Ask any vehicle electrical expert and they will tell you splice tap connections are not reliable. They use plug adapters that snap into place or butt end connections that are properly crimped and covered with tubing.
There is no "rig" at the battery. It's a dedicated 12v line that its only purpose is to power the trailer harness, nothing else. If the trailer wiring shorts, it pops the fuse in the line which is located near the battery. Nothing inside the vehicle gets shorted.
With Mazda's connection, if something goes bad, it can short out other things inside of the vehicle since it is not a dedicated line and it is going inside the Mazda panel.
We will have to agree to disagree on this topic. Like I said, Mazda is not in the trailer towing business so whatever it makes for towing, it most likely sources out or it is an afterthought.
That is the better setup. So Mazda does use a plug & play design setup in Canada but the US version gets shafted with the splicing.
Any way to get the Canadian Mazda wiring harness purchased and sent to the US?
Just like the CX5 in Canada gets paddle shifters on the GT while the US version does not.
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- 2017 CX-5 GT AWD
Yes, we will disagree.
The aftermarket solution has to be connected at the battery. So the module powered 24/7 and you are tapped at the battery. Maybe not a vampire tap, but still not my ideal solution.
And if the trailer wiring shorts with the mazda setup, the module is designed to shutdown. If that were to fail, then fusebox fuse blows. Pick your poison - fuse inside the car, or fuse under the hood.
And if i saw someone using butt crimp connectors in a car, they would not be doing my wiring. Those are the worst connectors possible. If a splice is needed it should be soldered. Sorry, butt connectors are not professional and not the sign of an electrical expert.
I agree that snap in plugs are more expensive and a preferred way to go for ease of install.
I think we have beat this horse though. As long as you are happy with your choice, that is all that matters.
I've posted on this subject somewhere in the past with my experience with the Tekonsha kit for my 2014 cx-5.I chose it over the factory kit because it doesn't require tapping into the wires at the lights but has connectors that plug between the car's wiring harness plugs and the taillights, so no insulation is punctured.The box is powered by the battery but instead of running the heavy power wire all the way to the battery I installed 15 A rated (with it's own 15 A fuse) "cigarette lighter plug" that can be plugged into the 20 A fused rear power port by the rear hatch.I just plug it in when towing and the rest of the time the wire and plug is stowed in the spare tire well.
********* NOTE *** I have not towed with it yet (didn't need to tow afterall at the time) but it does check out functionally using a little plug in tester.Don't have a good way to test it under full load without hooking up a trailer.We'll see when the time comes. Just something to consider.
But two main points for me was 1) having the trailer isolated from the car's wiring by means of a control module and 2) not having to puncture any insulation on any wiring.The factory kit did not address both points and might have even been more expensive. Good luck
********* NOTE *** I have not towed with it yet (didn't need to tow afterall at the time) but it does check out functionally using a little plug in tester.Don't have a good way to test it under full load without hooking up a trailer.We'll see when the time comes. Just something to consider.
But two main points for me was 1) having the trailer isolated from the car's wiring by means of a control module and 2) not having to puncture any insulation on any wiring.The factory kit did not address both points and might have even been more expensive. Good luck
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- 2017 CX-5 GT AWD
The factory kit does isolate now - maybe not in the past, but the 2017/18 kit does. It has a similar module, so the taps are just to detect when signaling is happening.
Do you have to puncture/remove insulation to "tap" the signal? Or is it at the connector?
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- 2017 CX-5 GT AWD
Instructions are here
https://www.mazdaparts.org/mazdaq-cx5-trailer-hitch-wiring-harness-kit.html
Yes, you have to cut back the tubing that group of wires to make room for the taps. the tubing is loose, and small scissors work.
Thank you. I don't like using T-taps like on page 13. I wish they used another connector inline instead
I like that you don't have to run power all the way to the battery though.
I wish there was an option that made all of the non-ground connections at the connectors, and didn't require running a wire the full length of the vehicle. I haven't seen any picture instructions on running the wire to the battery.
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- 2017 CX-5 GT AWD
Thank you. I don't like using T-taps like on page 13. I wish they used another connector inline instead
I like that you don't have to run power all the way to the battery though.
I wish there was an option that made all of the non-ground connections at the connectors, and didn't require running a wire the full length of the vehicle. I haven't seen any picture instructions on running the wire to the battery.
Those are the options - factory harness has taps, after market requires wire to the battery.
