Yeah, also a retired electronic engineer with 45 years of experience here...
Note that I simply said "ground strap". I know it's a negative 'ground' chassis. My point is that the engine block is already at negative potential based on the factory "ground straps". Adding another strap might...
Something must be wrong here. After all the engine block *IS* already grounded (even if not perfectly). I cannot believe there are 5+amps flowing through these grounds.
TPMS system is required by law in the US (not sure about Canada). First gen CX-5s used wheel speed sensors to detect differences in wheel rotations, but 2nd gen and on use TPMS sensors in each wheel.
Take a look at @sm1ke 's post here: 2016~2023 - CX-9 Rear diff failure at 113k kms (70k mi) Looks like $1000 for labor to replace, plus the cost of a diff/carrier. Seems like your $2600+ for a used part is excessive.
The chances are that this is simply brake pad material baked onto the disc rotors, possibly due to heavy braking followed by holding the brakes on while the discs are hot.
You could try one (or both) of two things. First, redo the brake bedding procedure of (on a deserted straight road)...
It will be a metric nut. If you have calipers (or even a ruler) measure the diameter of the bolt (or inside diameter of the other side nut). Chances are it's 5mm, if so, you'll need an M5 nut.
The high beams are used at lower power for DRLs. So, replacing the high beams with LEDs will cause flickering, possibly codes, and other nasties. Replacing the low beams (presuming you have projector low beams) will be fine, though.
That has been my experience too, on other cars. And it also leads me to doubt what the dealer was saying was true/accurate.
I would also agree with the "remove the headlight, and go over all possible seams where a leak could occur" idea.
OK, so I'm stepping back a little from my statement above...
Last night I had occasion to drive the wife's CX-5 again. What I DID notice as a difference to my CX-50, was that the initial 'bite' of the brakes was an appreciable way down the brake travel from that in the -50. Once the brakes...
I don't notice much (if any) difference between the 'softness' of our CX-5 vs CX-50. Also, people complain about the CX-50 brakes too, so I doubt that swapping anything other than changing the pads themselves (with aftermarket), will make an appreciable difference.
Personally, I like the...
Having had CX-5's since 2013 (still have them), and my CX-50 since 2022, let me comment...
The CX-5 has more sound deadening and is quieter, so it, IMO, makes the ride feel better than the CX-50, simply because the road imperfections are not heard as much. In actuality the ride is not that much...