How would you repair this wiring harness?

[ErrorMargin]

A previous owner tapped into the wiring harness with a T-Tap to get power for something (something that is no longer there), and now I have two partial cuts in the black and yellow power wire for the left tail light. The cuts are circled in yellow in the picture below.

The taillight is currently working fine and it seems that very little if any of the conductor wires under the insulation were severed.

I have the engine out, so it will never be easier for me to take action on this.

What would you do?

1. Cut out that section, solder in a patch and cover it with heat shrink?

OR

2. Wrap it with electrical tape and call it day? If you suggest this option, would you put some dielectric grease or something on the cuts to help prevent corrosion?

OR

??

[wazzz]

I would do number 1 if that's bad cuts, otherwise number 2.
Also, this black / yellow wire is not feeding the taillight but the brake light. So once you've fix it you want to check that both brake lights work.

[dannobee]

1. Don't solder in anything. It's solderless connectors (with the shrink tubing built in) or replace the wire. If the strands of wires are intact, how close is the nearest terminal, where you can carefully remove the terminal from the socket and slip over a piece of shrink tubing?

2. In this case, I'd probably carefully reshape the insulation for looks and apply a few coats of liquid tape so that it's as inconspicuous as possible. "Normal" electrical tape will look ratty after a few months in the engine compartment.

https://www.amazon.com/Permatex-85120-Liquid-Electrical-Tape/dp/B003ERU04W?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&smid=ATVPDKIKX0DER&th=1

[rwest]

I would agree that if the wire inside is intact, any soldering or cutting and putting in a butt connector will likely not last as long as just repairing the insulation.

So unless you can replace the whole wire from connector to connector in the harness, using shrink tubing, liquid repair product or electrical tape is going to be the next best way.

[John W.]

There’s two types of dielectric grease conductive and nonconductive. Use the conductive one.

As for soldering, it makes the best electrical connection but solder joints can crack if they’re subjected to vibration. In the satellite world where you can’t repair it, we’d solder and then make sure the wires are securely held in place to avoid vibration.

[PeteKz]

For something like that I use stuff called "liquid electrical tape." It's basically vinyl in a can with a strong solvent to keep it liquid. Paint it on thick enough to cover those cuts.

[yelcab1]

"liquid electrical tape."

[chrismorse]

It will never be easier to get this done.
Put a magnifying glass on it and see if some of the strands have been cut by the vampire clip.
Gently flex the wire to determine if the "strength" of the wire has been reduced by the afore mentioned Molestation of the wire. If it seems to flex/bend/hinge at one or both of the locations, it is time to cut out the section of the wire, unless you can get to an end connector, then replace that section, solder and heat shrink x2 to protect and stiffen the repair section to reduce the potential flex/failure of the joint.
If you cannnot disassemble an end connector to slide one or two pieces of shrink tube over the prior areas of connection, areas, then liquid tape is perhaps a better fix than ratty looking tape.
Murphy has taught me that the fewer the joints, the less likely the wire/pipe is prone to failure.
A POX on the miscreant that violated the integrity of your wiring harness,
FIE,
chris

[ErrorMargin]

Thanks to everyone for the great advice!

I cleaned up the cuts with contact cleaner and gentle brushing with a toothbrush so I could get a good look at the damage, see picture below.

The damage was minimal and the wire had good strength, so I used a toothpick to fill the cuts with liquid electrical tape. After it cured I wrapped the whole bundle with wire harness tape.

Originally Posted by chrismorse

A POX on the miscreant that violated the integrity of your wiring harness,
FIE,
chris

Could not agree more!!!

[Brian Cameron]

A good alternative to electrical tape is fusion tape aka F4 tape. Silicone based, stretchy, self-fusing. Holds well where electrical tape just starts losing adhesion and coming off.