Owning a low volume production car can have its drawbacks...

[Hugh Jassol]

My wife and I have greatly enjoyed our manual trans 2023 Blackwing 4 since we got it. I'll spare you all the gory details, but a few months ago we got a rodent in our garage. So I put out a number of traps, poison, etc. to kill the rat bastard. Those worked, but before it croaked it chewed on some coolant lines, and far worse, also chewed on a number of the harnesses. Primarily, the main ECM harness, and the main ABS harness. I had the car towed over to our local dealership. And that's when I found out how hard it is to get some of those harnesses from Cadillac. The ABS harness took three weeks, but according to the dealership the ECM harness is unavailable, and on "indefinite back order" from Cadillac. Just swell.
The dealership is going to try to repair the damaged areas of the harness. For some reason, this rodent apparently preferred the insulation close to the connectors. They're hoping to trim back the wires in those areas and re-pin the connectors. Just swell. The dealership was able to get my insurance to cover both the cost of the ECM harness repair, as well as the eventual replacement of the harness if it ever becomes available. BTW, the labor estimate to replace the harness is over 30 hours. The total estimate for the damage from ONE stupid rat is at $18,000! Needless to say, my garage is now a death zone for any of his rodent friends that might think about entering.
I'm skeptical that the ECM harness will ever be available. I'm working with the parts department to see if the harness is one-year specific, but if a 2023 harness isn't currently available, it's hard to imagine that it will be in the future.

 

[668LT4]

Are the harnesses different than the non-Blackwing cars?

We ran into rabbit trouble - yes, rabbit - last year with my daughter's Kia Soul. I'll skip the bulk of the story, and the photo with an arrow rammed through its neck in the corner of the garage. The first repair was about 3k, and we paid our $500 deductible. Moved the car into the garage (don't have an extra bay, but the L-shaped 3 car fits a 4th rather easily, but I have to move my truck to wiggle it in an out). Low and behold one day my daughter takes the car out and leaves it out front for a few hours after her errands. This is probably 1 month after the initial repair. We pull the car in to the garage ahead of a large snow storm. The next day, my wife comes in scared after taking the dog out through the garage. "Something is in the Kia's engine bay". Open the hood, fu*$ing rabbit. Got in the car outside and just drove right in when we parked it. We channeled Chaz Palminteri's "Now youz can't leave" from Bronx Tale, and after some time we finally corralled that little bastard. The damage the 2nd time was not as bad, and the shop agreed to fix it for $500, so we did not file a second claim. $1000 and a lot of headache.

The shop told me Audis and Kias are the worst, due to some kind of soy used in the harness wrap.

 

[KatyTxCT5V]

Wiring harnesses are not a common “routine maintenance” item on any brand. When a rat ate through one on my 6 month old 2019 Audi A7, it took about 7 weeks to get another one and get it back. I don’t remember all the costs and labor hours. It was in my garage when damage happened.

I had a 2016 Yukon always parked outside and one morning I smelled gas by the rear door while loading my laptop bag. Drove it straight to the dealership and they found 3 areas where a rat ate through the gas vapor recovery line! I would have thought the smell of gas would deter them, nope! Took about two weeks to replace and they had to drain the gas to drop the tank for attachment. Then I added “one bite sticks” to outdoor traps and haven’t had anymore issues except picking up a dead rat around the house once in a while.

I installed a mini split in my garage and all new special door rails along with extra insulation around each door. My 3 bays are locked tight now and no more rodents or spiders. I don’t even see cobwebs in the ceiling areas.

 

[Finally-a-V]

Out here in AZ, we have problems with pack rats. They will tear up a car in short order. Most people here who have to park outside will leave some kind of light under the car (under the engine) during the night. Some use shop lights, some Christmas lights, even just a bare light bulb. Seems the light deters them. I'm not sure it would work on other critters in other areas, but food for thought. (Yes, pun intended)

 

[rubberduck]

A friend had a rat wiring harness issue and the repair involved a new harness and they wrapped over it with capsaicin tape.

 

[ngoni]

I'm making a list of supplies for when my car arrives. "Rat poison" was not on my bingo card. Thanks for this thread though!

 

[rdollie]

My wife and I have greatly enjoyed our manual trans 2023 Blackwing 4 since we got it. I'll spare you all the gory details, but a few months ago we got a rodent in our garage. So I put out a number of traps, poison, etc. to kill the rat bastard. Those worked, but before it croaked it chewed on some coolant lines, and far worse, also chewed on a number of the harnesses. Primarily, the main ECM harness, and the main ABS harness. I had the car towed over to our local dealership. And that's when I found out how hard it is to get some of those harnesses from Cadillac. The ABS harness took three weeks, but according to the dealership the ECM harness is unavailable, and on "indefinite back order" from Cadillac. Just swell.
The dealership is going to try to repair the damaged areas of the harness. For some reason, this rodent apparently preferred the insulation close to the connectors. They're hoping to trim back the wires in those areas and re-pin the connectors. Just swell. The dealership was able to get my insurance to cover both the cost of the ECM harness repair, as well as the eventual replacement of the harness if it ever becomes available. BTW, the labor estimate to replace the harness is over 30 hours. The total estimate for the damage from ONE stupid rat is at $18,000! Needless to say, my garage is now a death zone for any of his rodent friends that might think about entering.
I'm skeptical that the ECM harness will ever be available. I'm working with the parts department to see if the harness is one-year specific, but if a 2023 harness isn't currently available, it's hard to imagine that it will be in the future.

Maybe search junk yards online? It will be some work to extract a harness but probably a lot quicker.

 

[Exia]

Take a look at how long it takes to repair any vehicle. A low volume car is no different from a high volume. The manufacturer orders X amount of parts to fulfill new builds and should also keep a supply for repairs of existing vehicles. The percentage spread is the same, you wouldn't be any better off if they built 50k Blackwings.

GM doesn't want to stock a large amount of spare parts that sit and if one of many suppliers have an issue you end up with a back order.

The C8 Corvette currently had a national backorder on TPMS sensors but obviously has no issue getting any to build them.

 

[Hugh Jassol]

Just to give folks a quick update: The ABS harness that was ordered in late October finally showed up. The dealership is replacing that harness, and was approved by my insurance to repair the main ECM harness until/if the new one shows up. The harness is not only model-year specific, but also VIN specific. The parts department has issued a request to GM to have a part number assigned, which is frustrating as hell since they can show me the harness on an exploded parts diagram, there's just no PN identified. The lead guy in parts has been with GM for a long time, he said this is only the second time he's seen it. The only other time was on a brand new car that GM hadn't released PN's for.
Been driving a crappy little Nissan Altima for the last seven weeks, starting to forget what it's like to own a fun driving car.

 

[ngoni]

That's crazy that the harness is VIN specific. They must only include wiring for modules that you optioned instead of making a standard harness with a few terminated plugs around the bay for things that aren't on the car.

 

[Dirkbg]

It's beyond something I would attempt to do, but I watched a youtube video a while back where HumbleMechanic made his own custom harness to adapt an Audi RS3 engine into his Golf R. If the wiring is just damaged by rodents, it probably wouldn't be difficult for a mechanic with wiring knowledge to simply remove and replace the damaged wires on a section of harness.

This is the video if you're interested in what goes into a rewiring project