For many just lifting the hood of a modern automobile and peering into a jam packed engine compartment is enough to prevent them from performing any maintenance or repairs on their own vehicles. Unfortunately never lifting the hood results in missed maintenance that is still the responsibility of the vehicle owner. You still have to check the oil sometimes!
Remember that cramped engine compartment is indicative of every other area in the vehicle where equipment is placed. Modern engineering allows three dimensional modeling of all spaces and computers can be used to design parts that fit into these spaces with little room to spare.
I was recently reminded of just how tight vehicle designs are when I was replacing the airbag control module in a late model medium size SUV. This module was located in the centre of the vehicle close to the floor in the area referred to as the console between the front seats. Your cup holders, gear shifter and possibly parking brake are generally located here.
Restraint or airbag control modules are generally located low and in the centre of the vehicle. All the better to keep them from harm's way in an accident. They are essentially the black box of a modern automobile. Many of them contain an event data recorder that stores information from many vehicle sensors at the time of an accident. This box also continuously processes a bunch of data and in the event of an accident the decision is made here to deploy airbags (front airbags, side airbags, curtain airbags), and seat belt retractors. It may even initiate a 911 call after the accident.
After an accident where any of your safety systems were deployed this module is replaced. The process of replacement in this case is a physical replacement as well as a computer learning, coding, or programming procedure. The new module has to be told what type of vehicle it is being installed in and what options the vehicle has. Are there only front airbags, or are there side airbags or maybe curtain airbags as well?
So back to the physical removal. Remove left instrument panel lower finish panel. Remove right instrument panel lower finish panel. Remove the floor console upper trim panel. Remove the right and left floor console finish panel. Yay! I can see the module ….along with a bunch of other modules all closely mounted to my target module as well as a gear shift mechanism and a bunch of electrical wiring. There is barely an inch of empty space.
Digging into my box of tiny tools I gradually find a way to extricate the module without taking apart the whole vehicle.
The equipment packaging in this console is impressive. The driver and passenger may be impressed by how well this console area supports their fancy lattes but your mechanic is impressed by how much stuff can be hidden underneath it.