What's your preferred way to splice into a harness?

Need to splice a trailer harness into my VW GTI. What's your preferred method? Crimped half barrel? Other crimped connectors? Twist and solder? Other?

 

For something like that I prefer to buy a pre-made plug and play harness.

If I absolutely have to splice, it depends on the environments the splice will live in.

If its going to be inside the vehicle protected from the elements, I'll do crimped connectors.

If its going to be exposed at all I will solder and heat shrink it.

 

Having done it both ways, pre-made plug and play harnesses are the way to go. It is so much easier it's ridiculous.

 

Scotch locks.

 

solder and heat shrink, only. and an absolute minimum amount of solder possible: the joint will flex, and if the solder is the strongest/stiffest component then the solder will break.

 

someone, or some company will make a plug n play harness, or "break out" harness, that taps the current wiring, and fuse system of the auto. do that above all else. If I had to guess, I would venture to say, VW probably has an OEM Accessory plug n play harness for your application. Ski

 

Looks like you really want to use a plug and play harness. Go here and select your year to see if it requires an interface module or not. Just tapping in may not work.

https://www.etrailer.com/vm/Volkswagen/Golf/t1

 

Beating a dead horse but please don't cut the harness if you're asking this question.

Use something plug and play as above.

 

I don't want to cut my harness, but apparently there is no plug and play harness for a Mk7 GTI, even though there is one for an R and a normal Golf of the same gen and a Mk6 GTI.

Would it be possible to make a plug and play? Could I buy an oem connector? Where would I find a piggyback connector like the ones used on motorcycle ECU plugins?

 

https://www.golfmk7.com/forums/index.php?threads/wiring-up-trailer-lights.334389/

 

Hopefully your plug and play will be easier than adding the trailer brake controller connector was in my 2013 Touareg. Nothing like laying on your back fishing around under the dash for 2 hours trying to figure out where they decided to hide the foam-covered connector that day. It isn't in a consistent location, and you have to find it by feel. That is after you have removed the under-dash cover and fuse panel cover just to get access. The ones up by the fuse panel are easiest because you can actually see them, but of course mine wasn't there.

 

For most automotive wiring that's exposed to any kind of weather, I've started using the crimp connectors that include heat shrink and a sealer built in, easier than solder and heat shrink. Hardware stores, Harbor Freight, etc. Calterm® Heat Shrink Terminal Kit at Menards®

 

Properly crimped fittings for anything exposed to vibrations.

Solder is not approved in many industries unless backed by crimped fittings. The essential element is good crimp dies and tooling and good fittings.

 

Those are nice too. I've used them a few times.

 

+100. Soldering for connections that are susceptible or exposed to vibration is a horrible idea. There is a technical standard IPC-620, which effectively mandates full-cycle crimp connectors for applications like this - to achieve long term reliability.

Granted, no one wiring a trailer harness is looking up IPC or likely buying a $3-500 T&B/Stakon crimper. So… +1 on plug and play harness or just shrugs, $30 crimpers and heat shrink are likely good enough.