DRIVER A 5P8631 - Caterpillar

Service Magazine; June 23, 1986; Page 6; "Hydraulic And Coolant Flow Switches in Electronic Monitoring System Can Be Damaged By Incorrect Testing."When testing sensing switches such as pressure, temperature, flow level and other switches that provide input to monitor panels (EMS, CMS, Excavator Monitor), use only a 6V7800 or 6V7070 Digital Multimeter. This also applies to backup alarm switches too. The use of continuity testers like an 8T0500 or an analog type multimeter can cause a momentary surge of current that may damage these switches. Continuity testers should only be used when testing harnesses, fuses, and circuit breakers for open circuits.