question about power steps

Am having intermittent problems with our steps on the below listed rig. Sometimes they work, sometimes they don't. Very common, I know. I crawled under the rig tonight and unplugged the connection between the batteries and the steps. Banged it together a bit, didnt see any corrosion or foreign material in the plug ends. Plugged it back in and eureka! It works. Is there a spray I can hit the plug with to keep the plugs talking to one another? Can't help but think the plug is the culprit, at least in my case.