PUMP GP-PS-BSC-V 20R7880 - Caterpillar

Understanding Causes Of Blown Fuses And Tripped Circuit Breakers and Understanding "Shorts," "Opens" and "Intermittents in this issue. Shorts-to-ground, either continuous or intermittent, may be difficult to locate especially when they blow fuses or trips breakers. The following procedure may be helpful to locate a short-to-ground that blows fuses or trips breakers.
1. Disconnect one wire from the applicable circuit breaker or remove the fuse.2. Temporarily connect a 9W1280 (24V) Lamp (or any 35 to 90 watt lamp) across (parallel to) the fuse holder or circuit breaker. Be sure temporary connections are reliable and will not cause shorts (unwanted connections).3. If the short is present, this lamp will be "on."4. To find the actual location of the short, disconnect, move, push/pull, and/or disturb the wiring and components in the effected circuit until the light blinks "on or off" according to physical motion.