Comment by loopies
16 hours ago
What you want is the service manual. Owner manual should be implicit. OBD port can work for some cars, for some of the data. But other cars do have specialized gear they require to either access either reset some stuff in some of the car's computers.
Yeah the owners and service manuals are two very very different things. You won't be performing much maintenance with the owners manual besides the absolute basics, like checking your oil.
The cheap OBD2 readers lack the vast majority of data and tools you would want to use for service as well.
There are aftermarket options but most manufacturers want you to subscribe to their service tools - often charged per monthly plus an additional a fee per VIN it touches. These cost in the hundreds to thousands. It can be pretty frustrating as a shadetree mechanic.
Notably, some vehicles like the Toyota Highlander you can’t even figure out when you need to change the spark plugs, let alone what kind of spark plugs you need from the owners manual.
Theoretically, they are to be replaced at 120k miles (!!) but they won’t even tell you that in the owners manual.
Insane.
It is, yeah. The owners manual for my current vehicle seems to mostly contain walkthroughs about the infotainment and other tech features. The section related to maintenance is tiny in comparison.
You're probably aware of this already but luckily a lot of service manuals can be found online in PDF form.
Somewhat related but I was going through an older relatives belongings not too long ago to help cleanup and found a bunch of old manuals for various household things. The detail included in them was beautiful to see - full wiring diagrams, mechanical diagrams, etc.
2 replies →
The change interval is in the Warranty and Maintenance Guide, not in the main owner’s manual. (This is still part of the in-glovebox manuals, not a service-center manual.)
One example: https://assets.sia.toyota.com/publications/en/omms-s/T-MMS-1...
Sadly service manuals aren’t commonly sold anymore and you need a subscription to a website to access factory service manuals.
It’s a shame, I use to buy the service manual when I bought the car.
Reading codes is only part of it. For the last quarter century or so (some manufacturers more than others) if you replace certain components (radio, any computer module) you need to update the ECU to recognize the new component. This requires proprietary software and in many cases proprietary hardware as well. These "features" are marketed as an "anti-theft" mechanism. This renders some repairs basically impossible for the end user to perform.
The fact that they've been allowed to build systems like that is appalling.