Final answer:
In the field of engineering, hydraulic pump low pressure lights turn on when pressure falls below a certain threshold, often around 1,500 to 2,000 psi, to alert the operator of potential hydraulic system issues.
Step-by-step explanation:
The question regarding auxiliary and utility hydraulic pump low pressure lights is based in the field of engineering, specifically concerning the monitoring systems within hydraulic systems. Generally, these low pressure lights will activate to alert the operator when the hydraulic pressure falls below a certain threshold. Despite the question not providing a specific pressure value at which the lights come on, in aircraft systems, for instance, the lights typically activate somewhere in the range of 1,500 to 2,000 psi (pounds per square inch) depending on the specific design requirements of the system.
It's important to consult the aircraft's maintenance manual or the system design specifications for the exact pressure value. The pressure at which the low pressure light is triggered is an important safety feature, as it informs the pilot or operator of potential issues within the hydraulic system that may affect its performance or lead to a failure if not addressed.