Why Does the Replacement Bulb # A1157B Illuminate Bright or Dim Depending on Orientation

Published 06/12/2015

Question:

When I insert 1157 bulbs in Peterson trailer lights, the bulbs get brighter or dimmer depending on which way I insert them. Why is that?

asked by: Burt J

Expert Reply:

The # A1157B that you referenced is a dual intensity bulb. Depending on which circuit you connect to on the light you could illuminate either the low or high intensity.

What I would recommend you do is activate the running lights of the trailer you are installing this bulb into and then install this bulb in the orientation activates the dimmer illumination. Then check to make sure it gets brighter when the brakes are applied.

expert reply by: Jameson C