ABS / Brake Light

Been through what seems like 100 posts and no luck. Here's the deal. I have my ABS and Brake lights on (don't flicker). They turn on when the key is in the run position and stay on all of the time. There is no speedometer fluctuations (spedo works fine). I have already replaced the rear speed sensor. I had it diagnosed by the dealer when I brought it in to have some recall work done and they said the brake fluid level sensor was bad. So I replaced that... exact same issue still. My question is how can I diagnose this issue further, and how can I fix it. Thanks.