NEED HELP WITH TACH

[10SecondHatch]

i have a 5 in tach from autometer . i folled the instructions and it work fine at idle shift light and everything so i set my shift point to see if the light came on and once i got past 3000 it starts jumping around all over the place and my light started glowing red .anybody have this problem or any suggestions

 

[Gixxer750]

i have a 5 in tach from autometer . i folled the instructions and it work fine at idle shift light and everything so i set my shift point to see if the light came on and once i got past 3000 it starts jumping around all over the place and my light started glowing red .anybody have this problem or any suggestions

Re-check the wires, make sure it is a good connection to the negative on the coil.