I have a 02 Ram1500 2wd rear ABS only with about 61K miles. Sometimes when on a trip and I get the truck up to 75-80 mph the brake and ABS warning lights will come on. The Speedo still works fine, brakes will stop the truck fine. If I stop the truck, turn off the ignition and re-start the truck the lights go out. The little engine light never comes on so no codes to check. Any thoughts or clues what might be causing the problem? It doesnt happen every time I go above 75, just sometimes.

 

I think the first thing I would do is check all the connectors for the system, starting at the back. If any look corroded or any wires looked chafed, clean them up and repair. On the connector plugs, pack with silicone grease then plug them back together---keeps water and salt out.

 

Well there probally is a code in the cab controller so you should get a scanner on it to read that. Could be just the speed sensor though.