Sr20det charging issue :/

[247_c2c]

So I can't seem to figure this out when I'm driving about 65 the brake light and battery light turns off but when I'm just cruising around town they are turned on... I have my battery ran to the trunk with standard size battery cable but I just started to do this when I switched over the upper harness to a wiring specialties harness...

Any input would Help thanks!!