abs light on wont fail m.o.t
yes it will.
the ABS light must illuminate when ignition is turned on, then the ABS light must turn off correctly as per the vehicles testing procedure.
If the ABS light remains on it IS an MOT fail.
If the tester knows the car has ABS, (its not difficult to know) then it will also fail if the ABS light never come on when ignition is turned on.
the text below can be found on the
http://www.motinfo.gov.uk/htdocs/m3s03000401.htm
method of inspection:
1. If the vehicle is fitted with an anti-lock braking system, check that
a. a warning lamp is fitted
b. the lamp illuminates
c. the lamp follows the correct sequence of operation
d. does not indicate a fault. (ie stays illuminated after test procedure)
Reason for rejection / fail:
The warning lamp
a. is missing
b. does not illuminate
c. does not follow the correct sequence of operation
d. indicates an ABS fault. (ie stays illuminated after test procedure)