I have 03 dodge ram 5.7 I have been having some serious issues with abs/brake light combo lighting up.I used a good code reader ,because it didnt throw any engine codes found 5 abs codes which were 25 LF cir Mal, 21 RF cir mal , 27 LF sensor erratic, 0 internal malfunction. 90 LF sensor shorted. I have had this happen a few months ago , the abs/brake combo of lights showed up then i would get nobus on my speedometer and a brief p0500 code i believe it went right away but that only happened a few times . I also had a close call when i was driving the lights came on and my brake would not work then they finally just locked up this which also happened once . Anybody have any ideas what this could be my concern is is the abs module is going bad. Any help or ways to troubleshoot to narrow down would be great
thanks
chris

 

Check the rear abs sensor on top of the differential. I had this happen on my 06 and it affected my cruise control ( cruise would only work between 67 and 73 mph) plus the abs light and brake light came on...Good luck

 

I would check the wire plug into the top of the ABS ECM. My ECM lost a few wire prongs due to corrosion. Now I have the ABS, Break, and Engine light on. Also have Code U1412. Waiting on the new ECM for the ABS (not the engine) to see if it fixes everything. I have a 2008 Ram 2500 HD with the 5.7L Auto trans.