Hey guys. My cars run fine with no problems whats so ever! I can turn the car on and no warning lights or nothing come up, then i can start it other times and get the ABS light come on and the speeddo moving up and down but this doesent affect the drive of the car, then i turn it off and on it goes back to normal?

what could this be?

many thanks

Harvey

 

Sounds like a poor ground or a slight short. With the speedo I would say it was the sending unit, but with the ABS also I'm saying a short. Have you checked your positive battery cable, the short one from the battery for corrosion? Be sure to look down under the casing from the connector, mine was down inside. I just replaced mine a couple months ago and before that I was getting an occasional ABS or restricted performance warning. It would also not restart sometimes unless I went into the trunk and wiggled the cable. I tried battery cable cleaner to no avail. Now I don't had any starting issues or indicators since. Hope this helps....

 

Ah, ok, Sorry to sound dumb.. so you saying I may need a new battery cable? The shorter one? sorry as Im only 22 and not seen this issue before

 

Maybe, maybe not, but its the cheapest check of the bunch. Simply go to your trunk and pop up the battery cover. Check for white corrosion build up. If you have some, you can purchase some battery cleaner from your favorite parts store. Also get a terminal cleaning brush, it looks like a large thimbul. If you've never used one, it breaks in half with the finger brush to clean the cable connector and the female part is for cleaning the battery terminal. After doing that, then you use your spray cleaner to get rid of any hidden residue. Be sure to spray a bit into the cable sleeve to try to get any corrosion inside it. Spray it, let it sit about a minute, it cleans up with some water and paper towels or rag. I use a spray bottle of water, be sure its clean and dry before reattaching the cables.
There's no guarantee this will work, but cleaning battery terminals is a simple must on any car to assure proper voltage throughout and cures many electrical issues.

 

I am pretty sure that the right rear abs sensor also drives the speedo, so I would start investigating there. Remove the sensor and clean the face of it. Check resistance through the sensor, people have reported 1.1 to 2.5 ohms as being ok. You can also check the continuity of the wiring from the abs module plug in the engine bay to the sensor. The wire near the sensor is known to break internally and give intermittent faults.