Who writes operating manuals? Engineers or lawyers?

Toyota’s Prius pioneered mass use of hybrid vehicles. One of us owns one and drives it to his and his family satisfaction. A recreational-educational family activity is look at the consumption monitor and enjoy the energy recuperation provided by the sheer inertia of the vehicle during decelerations and braking, knowing that not only the vehicles is not burning fuel but it is actually “generating” it.

A hybrid vehicle relies on batteries. It does happen that those go flat. The owner naturally takes a look at the operating manual (here quoted from the 2007 edition, Publication OM47556U).

Here something interesting takes place. The manual appears to be designed for purposes other than the solution of problems. It is full of warnings (in powerful attention-attracting bright yellow boxes), that are actually legal disclaimers and appear to be dictated not by the engineering, but by the legal department of Toyota. When it comes to jump starting the battery, an operation that may have to be performed in strenuous climate conditions that are oftentime accompanied by psychological tension, it is quite hard to figure out from the illustrations where one should connect the cable for recharging. Where should one attach the clamp of the jumper cables? The distracting warnings add to the difficulty of the task, inducing futher stress.

Given this, tou may think that it is wise to check the battery status from time to time, when things are calm. The journey through the manual is interesting. Go to p. 414, “Checking 12 volt battery condition.” The back door may not open. “If the back door does not open, see “if you cannot operate back door opener on page 376”. On pages 376, the first step is Opening the luggage storage box. For this, “See ‘Luggage storage box’ on page 314”.

A paper manual is not a hypertext and ought not to be written like a hypertext. It must be used efficiently precisely when power is out and paper is the last resource.

Suggested reading, Robert Pirsig, Zen and the art of motorcycle maintenance. There are beautiful pages in it on the ethics of manual writing.



Toyota manual Prius

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