Inside each of the hose fittings are little screen filters, make sure they are clean. Remove them and run clean water through the filters until they are clean.
Check to see if the pump motor is running. If it is not running, use your voltage meter to check the plug socket where it is plugged in. If there is power at the socket but the motor is not running, the motor is burned out and needs to be replaced.
If the motor is running and there is still no pressure to the sprinklers, there is a leak. It might not be a water leak. Air leaks can bleed the pressure and won’t allow the unit to function properly. Using your screwdriver, remove the screws holding the pump together. Where it comes apart there will be a main seal, and there should be a rubber gasket. Check the gasket for any rips or tears. If you find any, replace the gasket.
Secure the gasket area with Teflon paste. Coat the gasket with a heavy coating of Teflon paste. Join the two halves and screw them together. This should solve all air or water leaking problems.