Help: Freightliner FLD CEL & Buzzer

No that's not a switch, merely the reader port. You should have a switch on the dash that will flash your CEL and shutdown lights in a code to tell you what's wrong. BTW, you can't afford not to fix your water pump. They are cheap and easy to fix yourself on DD 60

 

Usually on that type dash, it's a black round push button switch.

 

You can "repair" the buzzer in your "Vigil Bar". In the back of the bar there is an opening. The buzzer is the 1" square thingy you should be able to see it. I believe the shroud comes apart and your replacement buzzer comes with instructions on "removal" and replacement. The Bendix Vigil Bar is very expensive to replace. If you are having signal light issues with it(which I know you are not) Freightliner has a "fix" for that as well.