General Tow bar electrics recommendation
- Thread starter fujoo
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General Tow bar electrics recommendation
I'd definitely get the bypass relay version the wires on most modern cars arnt thcik enough to directly support the extra voltage of running the wires directly from wires
However i would look to solder the trigger wires and not used scotch locks
However i would look to solder the trigger wires and not used scotch locks
fujoo There are basically four options: 7 pin or 13 pin, and with or without a bypass relay.
If you only intend to tow a simple trailer (so don't need power to fridges etc, as you would in a caravan), 7 pin is all you need. That connects indicators, brake and tail lights, and the rear fog. It does not connect a reversing light though.
The 13 pin plug adds to the above the reversing light, and power to the trailer. However, it also then needs extra wiring inside the car to connect this up.
On older cars (most likely over 15 years old or more now), you don't have to use a bypass relay, because the wires in the car to the lights etc are all thick enough to just 'tap into'. But the wiring on newer cars (inc the Panda) are hair-thin, and are not too happy at being asked to carry the extra current that trailer lights would take. The lights etc are controlled by a computer system ('CANbus'). The bypass replay is wired direct to the battery (via a fuse) and then uses 'triggers' from the thin wiring to make the relay operate the lights. Each trigger wire is connected to the cars wiring in the boot - but you have to be very sure you are cutting the correct wire to connect to. As Chris says above, best to avoid 'scothblock' connectors -- the simple plastic wire spices that clip over the existing wires and cut into them. because CANbus wires are so thin, these tend to break the wires! It is 'essential' with CANbus wiring to use a relay.
There is actually a fifth option (and this is what I shall be using) - which is to buy a wiring set that specific to the car. It does cost more, but instead of cutting into any wires, it uses the existing plugs/sockets within the cars wiring loom to extend to the trailer circuits. This means you don't have to try and work out which wire is which to cut into to connect the relay, and there is much less chance of things going wrong down the line. There is one kit out there where you don't even have to run a wire through the front wing to the battery, as is makes all the connections inside the car.
You will also see mention of 'PDC control' -- this is the optional rear parking sensors on the Panda. If you have the sensors, the kit includes an extra link in the wiring to disable the rear sensors when the trailer plug is in, to stop it beeping because theres a trailer right behind you.
Hope this helps.
If you only intend to tow a simple trailer (so don't need power to fridges etc, as you would in a caravan), 7 pin is all you need. That connects indicators, brake and tail lights, and the rear fog. It does not connect a reversing light though.
The 13 pin plug adds to the above the reversing light, and power to the trailer. However, it also then needs extra wiring inside the car to connect this up.
On older cars (most likely over 15 years old or more now), you don't have to use a bypass relay, because the wires in the car to the lights etc are all thick enough to just 'tap into'. But the wiring on newer cars (inc the Panda) are hair-thin, and are not too happy at being asked to carry the extra current that trailer lights would take. The lights etc are controlled by a computer system ('CANbus'). The bypass replay is wired direct to the battery (via a fuse) and then uses 'triggers' from the thin wiring to make the relay operate the lights. Each trigger wire is connected to the cars wiring in the boot - but you have to be very sure you are cutting the correct wire to connect to. As Chris says above, best to avoid 'scothblock' connectors -- the simple plastic wire spices that clip over the existing wires and cut into them. because CANbus wires are so thin, these tend to break the wires! It is 'essential' with CANbus wiring to use a relay.
There is actually a fifth option (and this is what I shall be using) - which is to buy a wiring set that specific to the car. It does cost more, but instead of cutting into any wires, it uses the existing plugs/sockets within the cars wiring loom to extend to the trailer circuits. This means you don't have to try and work out which wire is which to cut into to connect the relay, and there is much less chance of things going wrong down the line. There is one kit out there where you don't even have to run a wire through the front wing to the battery, as is makes all the connections inside the car.
You will also see mention of 'PDC control' -- this is the optional rear parking sensors on the Panda. If you have the sensors, the kit includes an extra link in the wiring to disable the rear sensors when the trailer plug is in, to stop it beeping because theres a trailer right behind you.
Hope this helps.
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Thats a very good price and better than the £220 i saw from the same 4x4 towbar. I might be buying that!
That’s a huge help—thank you so much. Can you give me the name of the kit that you don’t have to run the wire to the battery. I’m fitting this to my TA 4x4.
It’s the best price I’ve seen so far for a detachable tow bar and from what I can tell it’s Italian made.
