5 after elapse of a predetermined time period from the time t 2 the control computing section 10 reads the charging voltage vs 1 of the capacitor 58 at a time t 6 after the reading of the charging voltage vs 1 of the capacitor 58 is completed or after elapse of a predetermined time period from the time t 5 the control computing section 10 sets the signal vr at the high level to bring the second switch element 59 into a conductive on state in this manner the capacitor 58 is discharged to reset the charging voltage vs to 0 v fig3 is a timing chart of the internal combustion engine control apparatus according to the first embodiment of the present invention in the case where a discharge voltage vb of the spark plug 40 has an abnormality fig3 differs from fig2 referred to above in the discharge voltage vb mainly in an operation from a time t 3 u2032 to a time t 4 u2032 the operation at the times except for the time period from the time t 2 u2032 to the time t 3 u2032 is the same as that illustrated in fig2 and therefore the description thereof is herein omitted at the time t 3 u2032 when the magnetically induced voltage generated in the secondary coil 30 b exceeds a discharge voltage vb 2 in the spark discharge gap in the spark plug 40 the spark discharge is caused in the spark plug 40 as a result the secondary coil voltage v 2 rapidly converges to the glow arc discharge voltage the discharge voltage vb 2 illustrated in fig3 is larger than the.