headlight dim?

[GARTHXS]

so I installed a new lens and bulb on my 78 it has a special headlight bucket, and an 80g wiring harness, the low beam is dim and the rlu comes on and doesnt switch to high beam , I replaced the bulb and no difference, high beam does come on when turned on ??

[mxmikie]

sounds like a bad reserve lighting unit mine did the same thing so i bypassed the rlu