[code_duck]

I’ve had a couple of American cars and apparently year-by-year or even in the same model year the manufacturer changes the location of certain parts, which I didn’t expect. Mechanics and I have had trouble finding various parts like fan relays and cabin air filters.

[StillBored]

Mid year ECR's to fix problems are not uncommon, but tend to be fairly minor.

What source are you using for where a part is placed? I've seen similar things (relay is under drivers dash, when it reality its under the passenger seat or some nonsense like that) when using crappy documentation (chiltons, or similar which does a "teardown" on a single year and then sells it for the entire generation). I can't remember seeing these kinds of errors in actual manufacture/dealer shop manuals.

[code_duck]

I attempted to learn the locations by comparing it to other vehicles in non-official documentation or instructional videos online. I’m not sure what resources the mechanics have.

The fan relays, for instance. Apparently Chrysler moved the location between 2006 and 2008, and I had a 2007. In the 2007 models, apparently the relays are in one of three places. Actually four, as mine where is somewhere entirely different which was difficult to access without a lift.

Next, a cabin air filter for my 2015 vehicle. Two lube places have tried to replace t and been unable to find he location (they say it’s oke of two places). They said they think I don’t have one, which is contrary to what the manufacturer says.

[wil421]

This is pretty common. My 2017 and 2019 Jeep Grand Cherokee had small differences. My 2000 E46 also had small differences including having an Iron block that was switched to an Aluminum block. Not to mention small design choices like knobs, switches, and buttons.

Dont you want manufacturers to fix something mid production if they find an issue?

[code_duck]

My assumption was that the process was more rigid, and everything was thoroughly standardized and determined before the car went into production.