The Federal Motor Carrier Safety Administration (FMCSA), in conjunction with the Pipeline and Hazardous Materials Safety Administration (PHMSA), is issuing this safety advisory to provide notice of emergency discharge control equipment connected to and installed on cargo tank motor vehicles, which when improperly installed, do not operate correctly and can result in total loss of power to the cargo tank motor vehicle.  This revised safety advisory updates and replaces the previous advisory of the same title that was originally issued on November 25, 2015.