You can read them with a paper clip and an LED, have a search around this forum.
Robbie, are some 2.5’s equipped with the old type diagnostic socket as well as an OBDII port? I have an LED type “reader” for our earlier Mk2’s (we have two of them in the family) but thought that the Mazda generic type of diagnostic socket wasn’t fitted for the 2.5 onwards.
The 17 pin diagnostics plug remained on all NBs right through entire production along with the 16 pin which was introduced on facelift cars.
I don’t know if this is relevant but I have a 2.5 and I had the abs light come on. If I switched off and started again it did not come on again. Went to my local Mazda dealer for proper diagnostic and the result was “you need a new battery - nothing wrong with ABS system”
frog