If I have seen one tale of woe with engine fault codes I must have seen a hundred. And this has got me thinking.

The cookieman996 “YRV Misfire” (http://www.daihatsu-drivers.co.uk/node/16915) post about a misfire on a cylinder is a good example of a typical story of fault codes. Parts are swapped out and then the fault comes back so plainly the parts that were swapped out were not the problem then. This is not a good thing, and if I was the customer I would want my money back on the job, or a warranty claim on the new parts if the garage insisted their diagnosis was correct because the new parts must be defective then. The garage would get some grief if it were me.

Anyway.

The clue to all this angst about fault codes is in the name. It is a code. Subsequently it needs to be broken down but it seems the deciphering bit is not being done at all, or well enough at least, and some sort of blind faith is being applied that the code must be believed in its simplest form. Sure, the code number translates to a specific reference, but what actually is causing the fault still seems to be unanswered accurately. For me the code would be merely an aid to diagnosis and not the answer.

Looking at another posting by sx-turbo “urgent help, error code” (http://www.daihatsu-drivers.co.uk/node/16907) I would ignore that 10 error code. It is as stated related to starter signal, which one assumes is to do with the starter system. Plainly the fault is not a start problem. The code in my mind is a false positive and unrelated to the symptoms unless proven otherwise. It is a red herring.

Incidentally that 10 code had me puzzled because I had never heard of a two digit code and even chasing it up on the www was not straightforward. It turns out it is related to OBD1systems. Me and probably most of us deal in OBD2 systems with longer codes. So I learned something, which is always good.

So what am I saying about fault codes? They are useful but they aren't the whole story and using what is presented by the code needs an application of well grounded knowledge of the system, proving the fault, and a dab of intuition.

Whet do you reckon.

Regards