COVER AS-OIL PUMP 7G2250 - Caterpillar

System Operation Description:Use this procedure to troubleshoot a suspected problem with the circuit that is for the engine prelube solenoid or use this procedure if one of the diagnostic codes in Table 1 is active or easily repeated.
Table 1
Diagnostic Codes Table    
Description    Conditions which Generate this Code    System Response    
E233(3) Low Engine Pre-Lube Pressure     The prelubrication pressure is outside the expected pressure for the programmed delay time.     The code is logged.
The alarm output is activated.
The engine is prohibited from being started.
The Electronic Control Module (ECM) continues to energize the prelube pump relay.    
338-5 Engine Pre-Lube Pump Relay : Current Below Normal     While the output driver is off, the ECM detects an open in the circuit for the engine prelube solenoid for more than five seconds.     The code is logged.
The alarm output is activated.    
338-6 Engine Pre-Lube Pump Relay : Current Above Normal     While the output driver is on, the ECM detects a short in the circuit for the engine prelube solenoid for more than five seconds.     The code is logged.
The alarm output is activated.
The output driver automatically resets and the output driver continues to try to activate the circuit component.    
339-5 Engine Pre-Lube Pressure Switch : Current Below Normal     The ECM detects an open in the circuit for the circuit for the manual prelubrication switch.     The code is logged.
The alarm output is activated.    Note: The prelubrication system is an option on these engines. If Caterpillar did not supply the prelube system, the electronic control for the prelube system is disabled. The above diagnostic and event codes are also disabled.If the "Engine Pre-Lube Time Out Period" parameter is programmed for a time period of zero seconds, the diagnostic and event codes that are mentioned above are disabled. The engine will crank without the prelubrication.In order for the prelube system to be enabled, the "Engine Pre-Lube Time Out Period" parameter must be programmed for 120 seconds.The prelube pump will not operate if the emergency stop button is activated or if the engine speed is greater than 0 rpm.During the prestart, the ECM will energize the prelube pump before cranking the engine in order to provide lubrication to the engine bearings. If the prelubrication of the engine is required, the ECM will provide +Battery voltage to the prelube relay. The prelube relay provides pressurized air or gas to the prelube pump motor. The prelube pump pressurizes the engine's lubrication system with oil. After activation, the prelube system will operate until one of the following occurrences:
Activation of the prelubrication pressure switch
Completion of the programmed "Engine Pre-lube Time Out Period"
Activation of the emergency stop buttonThe ECM monitors the prelubrication pressure switch in order to verify adequate lubrication of the engine prior to start-up. The pressure switch is normally open. The pressure switch closes when the prelube pump raises the engine oil pressure to 9 3 kPa (1.3 0.4 psi). When the pressure switch closes, sufficient