Considering the general trend of sloppy wiring practices that I've encountered on cars over the years, I figured I'd make this little 'how to'. Hope it helps someone.

What you need to know before you attempt terminating-yellow means 10-12 gauge, blue means 14-16 gauge, red means 16-22 gauge. When in doubt, just use the color that fits the tightest on the stripped wire, without bending any of the strands back.

Needed tools-

Ratcheting crimpers-if you don't have ratcheting crimpers, you can't make a decent crimp. Get some, they are cheap. "Parts Express" sells, and ships them cheap.

Wire strippers

Cutters-your standard dykes will work, but the proper tool ones are 'flush cutters'. Cheap, and again, Parts Express carries these.

Time to go to work!

Pic of aforementioned tools-



Step 1-strip wire to proper length. Proper length is where very little to no wire is protruding from the non-insulated side of the connector that you're attaching, and no uninsulated wire can be seen hanging out of the insulated side of the connector. Take a look inside the connector, you'll see what the 'perfect' length is.



Picture below shows the wire/connector pre-crimp, you can see very little to no wire hanging out of the end.



Step 2-insert connector into the crimp tool. The side of the connector barrel with the split goes towards the male/small side of the crimp tool. Sqeeze the tool (ha ha), and it'll ratchet to the perfect tightness and release.



Pic of completed crimp-

 

Good job. I think people need to do better jobs at soldering. A good crimp is very important to.

 

I personally prefer to solder as my first choice. Ive never been a fan of crimping connections. Good write up for how to do it correctly though.

 

if its a really important joint, i take the stupid insulation off, crimp it, toss a little flux in the joint, heat it up and let it suck up some solder. then i use shrink tubing over the joint.

 

After you have crimped is a good practice to try to force the crimp with your fingers, pulling the wire and the terminal in opposite direction. A good crimp must withstand at this simple test.

And ABSOLUTELY, ABSOUTELY don't use economic "wire stripper and crimp tool", there is no way to make a good crimp with this tool.

 

Having a good crimping tool is important. I like soldering also.

 

^^^ This information is for the most basic crimped connection. If you want to be able to check how well your crimp has been done, use bare terminals instead of those plastic covered ones, and proper heat shrink for insulation. Remember to put the heat shrink on the wire before you crimp the connector, or you're out of luck...

High quality crimp tools are expensive and a lifetime investment. When you want to crimp pins for connectors, you will usually need to get the crimp tool that matches the line of connectors you intend to use. Metripack / Weatherpack/ Deutch Motorsport/ etc.... They are generally not interchangable. You'll also need a release tool that matches the connectors/ pins you select.

Most high end electrical harnesses use only crimping -- no solder -- because solder has the potential to weakens the wire where the solder ends, which causes failures.

 

Agreed, however there is no reason to use an uninsulated terminal to inspect for proper termination, as long as you used a quality crimp tool and a quality terminal that's the right size for the wire. As long as the wire is flush (or slightly protruding) from the end of the barrel and it passes the 'pull check', it's fine.