I have a 2000 ford ranger and the check engine light is on. I have taken it to two places (one local auto store, and an autozone in town) neither one can read the codes because when they plug in their code readers they just get an error. I know its not the readers because the local shops worked on other vehicles and on mine before but not now. What can/do I need to check to try to remedy this? I have already sprayed the connector with electrical connections cleaner and that did nothing, I am going to check and see if any wires have somehow came loose from the back of the connector but beyond that, I'm lost. ALSO!! I changed out my egr valve because it was throwing a code for that and the light is back on again (battery was disconnected for >1hour when I did the swap and the light was off for a day) but I obviously can't check the code due to the above problem, so my question on that is, it can't possibly be the same code can it? if it is what the fuck do I do then? Thanks!