In the process of rebuilding the brakes from hard lines out, during tear down I found all of the ABS Sensor plugs deteriorated beyond repair. I have new replacement harnesses on order and I am looking for the procedure to do the job.
From every thing I can find it is a cut and crimp new by wire color and heat shrink.
has anyone out there done this rehab before and are there any pitfalls to avoid in the process?

1999 Boxster Base

 

I had an ABS failure that was difficult to isolate, but finally narrowed it down to the right front harness by spinning each wheel and observing the wheel speed on the Durametric while wiggling the harness. I got the replacement from the dealer, and you are correct, it's a cut-and-crimp-and-heat-shrink operation. Because I was not super confident about getting it right on the first try, I left all the extra slack in the new harness and did not solder the crimp connections nor shrink the heat shrink -- now that I know it's all good I should finish the job.

The only caveat is just to take your time and care with finding a good splice location, and be careful when cutting the wires and cutting back the layers of insulation to expose the bare wire. I traced the harness back from the RF wheel well and found a place on the right side basically where the VIN is stamped, where there is actually an existing splice connection; I think the instructions indicated another place on the far opposite (LF) side of the cowling near the brake booster, but this was a good accessible location and allowed me to keep more stock wire length and more harness slack as "spare" in case of needing a re-do or re-try.

On my '98 Boxster the 20-year old wires' insulation under the front cowling was a little bit hardened; when I unraveled the wrapped insulation and pulled out the individual wires to cut them, there was a tendency for the insulation to crack and let some bare wire peek through the crack. I think I had to wrap a little bit of electrical tape on one or two spots where the insulation became compromised due to being manipulated. Oh, and don't forget to slide the shrink wrap tube on *before* you make the new connection, so that you can slide it over the connection afterwards and shrink it!

Here are a couple of "before" pictures I looked up from back then (2018) as I determined where to splice it in. (I realize yours may not be at the RF corner.) You can see where I found the existing join after I cut out a section of hard plastic insulation at the VIN stamp, and you can see how bending the wires a little bit caused some cracking of the individual wire insulation. Hope this helps a little.

The accessible segment of harness where a splice would be easiest.

Old insulation cracks easily when bent. (or did I nick it while cutting away the outer insulation?)

Where there's an existing connection -- I think I spliced on the inboard side of this so I got rid of the existing splice and the harness outboard of that.

Another angle.

 

Extremely helpful. Thanks for the pics.
I will be doing all 4 corners with the Porsche Repair Kits.

 

(deleted)

 

I have to do my 2007 now, any more information about this issue would help

 

You can buy the wiring harness for the ABS from Porsche. Even from Porsche it's a splice job. Porsche puts the splices pretty far up into the harness, if I recall correctly 2-3 feet in from the hub, both being up well beyond the wheel well. PITA job.

BTW on the early Boxsters (all 986 AFAIK) the left front ABS harness is left exposed outside the plastic fender liner at the rear of the fender well, right in line of rocks getting kicked off the LF tire. I put a piece of plastic split wire loom over mine to protect it. Such a dumb design.