Both the "Brake" light and ABS light remain on all the time. Not sure where to even begin looking for an issue as there are no issues with the brakes or ABS.

 

Forum members can help better knowing vehicle info you are asking about...?
If your equipment sticker is still readable you can find the ABS plus other info on your van, it's underside of hood over the battery

Mine's a 99 3500 extend cargo, 5.9l. It has 4 wheel ABS. My ABS and brake light have been on for a good 4 years, intermittently.
If the weather is cool (morning time) or wet they normally won't come on, but hot/dry weather like now here in nor Cal they tend to light up about mid morning till all day.
Not sure of the exact fix but thinking it's one or both of the front sensors is dirty or failing. never had an issue braking but ya the light can get annoying.
Also never wanted to pay the cost of new sensors as they are quite pricey. I have taken the sensor out of it's mounting place on the hub while inspecting or changing pads, and gently cleaned it and the orifice with good results that lasted for a while, they do get dirty with brake dust and such so may be as simple as a cleaning of the sensor and where it mounts if that is the case for you

You can tell if you have front sensors by looking at the soft rubber line going into your calipers, the ABS electrical harness will be clipped to that rubber line and attach nearby to the inside of the hub mount area.
If it's the rear causing the light, then I need to be educated too, no experience on that

 

Thank you for your response! My bad for not including vehicle information...1999 Ram 1500 Van with a 318. I will take a look at the sensors as you recommended. I have also heard part of the problem may come from a bad or dirty speed sensor in the rear differential. I will have to check that as well. Again, many thanks for your reply!

 

It's been a while so pardon my forgetfulness, The rear differential sensor was what I had found most common too. Seemed most others were also having some speedometer trouble along with it, but I wasn't.
I changed that rear sensor out first with no change and still lit up abs/brake light. It was not long after I had worked on the front brakes pad change and had cleaned up the front sensors too, for a short period of time the lights didn't come back on, then eventually did again.

It's not too expensive a part, just can't give you a yea or nay that it will definitely work so if it does let us know...?