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Sumitomo 2.3mm(090) Open Barrel Terminal Twists In Seat When Crimping

EFI Wiring Fundamentals

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Hi All,

I'm new to practical automotive wiring, but have a reasonable beginner base knowledge of electronics through my engineering degree. I'm attempting to repair some dodgy headlight wiring on my 1997 R33 Nissan Skyline GTST. This is reasonably simple in that it just involves running new wires, and crimping new terminals for the OEM fuse box and a body harness connector.

I'm trying to crimp what I believe are fairly standard Sumitomo 2.3mm(090) terminal (1500-0105) used in a variety of connectors. I've been trying to practice crimping them using a bunch of spare terminals I bought but have been struggling to get a consistent and professional result. I've been practicing on standard 3mm PVC wire of the following specifications which I believe is within the limits of the terminal.

Wire Specifications


Terminal Specifications


I'm using the second die labeled 2.0 in the Fujiya FA103 crimping pliers that my local automotive wiring store sold me.

The problem I'm having is as I begin to apply progressive pressure when crimping the open barrel section of the terminal, inevitably the force reaches a point where the terminal suddenly twists/rotates in the seat of the crimp tool, in spite of me trying my best to avoid this. This results in the w section of the tool no longer aligning properly with the terminal. Subsequently the tangs don't fold together evenly, and deformation of the terminal occurs. Trying different die sizes in the tool still seems to yield the same result.

It seems likely to me that there is something wrong with

1. My technique

2. My assessment of the wire/terminal/die-size.

3. My tooling

I'm hoping someone with more experience can shed light on what could be going wrong. I can try post some photos or a video of the crimping, but my phone camera quality isn't amazing.



Hello this is most likely because of the tooling, but i would like someone who is proficient in wiring to comment also

I get this if I don't get the terminal set in the crimper evenly. I usually start the crimp and make sure it stays in position (even / upright / straight / non-twisted), before I give it the final squeeze to complete the crimp.

Thanks all for the help! Just thought I would post an update. I ordered the Sargent 1026CT from mouser and that is providing much better crimps without any twisting while crimping or subsequent deformation.

Looks like it was the tooling. Appreciate your replies. Thanks.

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