An abnormality diagnosis apparatus for determining whether abnormality relating to execution of automatic activation has occurred in a timer circuit. The optical signal from the integrated-optic voltage sensor is conducted to a low voltage environment insulated from said HV environment and processed to provide a second electrical signal. Error correcting code results are recorded on the test data for the unscramble and scramble modes. For collars which do not include any collar stay pocket, or where a collar stay pocket is not desired to be used, the collar stay can include an adhesive on an outer surface thereof adapted for adhesive attachment to the inside surface of a collar.