21850623 Volvo.Penta Mixing chamber

Table 1
Diagnostic Codes Table    
Code and Description     Conditions which Generate this Code     System Response    
446-5 Air Shutdown Relay current below normal     The Electronic Control Module (ECM) detects low current in the circuit. The ECM can only detect this condition when the output driver is not activated.     The code is logged.    
446-6 Air Shutoff Relay short     The ECM detects excessive current flow in the circuit. The ECM can only detect this condition when the output driver is activated.    
E2087(3) Air Intake Shutoff Closed     The ECM detects an "Active" condition in the detection circuit that monitors the state of the air shutoff valves. The configurable parameter for the air shutoff system is set to "Installed".     The code is latched until power is cycled to the ECM. The process for starting the engine will be stopped and the process for starting the engine will be disabled. If engine rpm is present, the air shutoff relay will be activated.
The code is logged.    
E2088(1) Air Intake Shutoff Detection Circuit Detected but Not Installed     The ECM detects an "Active" condition in the detection circuit that monitors the state of the air shutoff valves. The configurable parameter for the air shutoff system is set to "Not Installed".     The code is logged.    A normally closed switch at the air shutoff valves will open when the air shutoff solenoid activates the air shutoff valve. The switch input to the ECM notifies the ECM that the air shutoff valves are closed. The ECM will not send injection signals to the injector solenoids until the switch inputs from the air shutoff valves indicate that the valves are open. If the circuit indicates that the air shutoff valves are closed, the ECM will generate the E2087 event code.Note: The air shutoff is optional. A programmable parameter needs to be set to "Installed" with Caterpillar Electronic Technician (ET) in order to enable the air shutoff system. If the air shutoff system is installed on the engine but the configurable parameter is not set to "Installed", the ECM will detect the air shutoff system through the normally closed switches on the air shutoff valves. If this happens the E2088(1) event code will be generated.The ECM has the ability to stop the engine in an emergency situation by shutting off the air supply to the engine. The ECM activates a relay which energizes two air shutoff solenoids. The solenoids trip the air shutoff valves.There are three conditions which can cause the ECM to activate the air shutoff:Engine Overspeed - The first condition occurs when the ECM detects an engine overspeed. During an engine overspeed, the ECM energizes the air shutoff relay. The ECM supplies voltage to the air shutoff relay for one second. The output of the relay will energize the air shutoff solenoids in order to shut down the engine. Once an event for the air shutoff system is activated, the event is latched until electrical power to the ECM system is cycled.Overspeed Verify Feature - The second condition occurs when the overspeed verify feature is initiated with Cat ET. This feature will energize the air shutoff relay when the engine speed is increased above 75 percent of the rated engine speed. The ECM supplies voltage to the air shutoff relay for one second during the shutdown. The overspeed verify feature can be initiated in order to test the operation of the air shutoff system.Remote Emergency Stop Switch - The third condition occurs when the remote emergency stop switch is activated. When the remote emergency stop switch is placed in the STOP position, the switch inputs at J1-23 and J1-28 are opened. The ECM supplies voltage to the air shutoff relay for one second during the shutdown. The remote emergency stop can be activated in order to test the operation of the air shutoff system.The air shutoff relay can also be activated without the aid of the ECM. When the customer's emergency stop switch is placed in the STOP position, voltage is supplied to the relay control for the ECM relay. The ECM relay removes electrical power from the ECM. Voltage is also supplied to the air shutoff timer. The air shutoff timer supplies voltage to the air shutoff relay for 2.5 seconds. This latches the air shutoff valves in the closed position. The timer has been placed in the circuit in order to prevent the shutoff solenoids from being powered for extended periods.After the air shutoff mechanism has been tripped the following actions must be taken in order to start the engine:
A manual reset of the valve mechanism is necessary.
Verify that the switches that detect air shutoff are closed.
Remove electrical power from the ECM for 3 seconds in order to reset any event codes that are latched.
Illustration 1 g01443822
Schematic for the air shutoff system
Illustration 2 g01444508
Location of the ECM connectors (1) J2/P2 ECM connectors (2) J1/P1 ECM connectors
Illustration 3 g01210157
Air shutoff mechanism (typical example) (3) Terminals for the air shutoff solenoid
Illustration 4 g01444514
P1 ECM connector (P1-23) Remote emergency stop (signal 1) (P1-28) Remote emergency stop (signal 2) (P1-52) +Battery (P1-53) +Battery (P1-55) +Battery (P1-56) Air shutoff switch (P1-63) −Battery (P1-65) −Battery (P1-67) −Battery (P1-70) Keyswitch
Illustration 5 g01444518
(P2-13) Digital return (P2-66) Drive for the air shutoff
Illustration 6 g01209281
Terminal locations for the air shutoff timer (1) +Battery (2) −Battery (3) Control (6) Load
Illustration 7 g01444669
Generator connector (Terminal 4) auxiliary power (Terminal 5) auxiliary power (Terminal 15) D