3582555 Volvo.Penta Gear

Table 1
Diagnostic Codes Table
Description Conditions which Generate this Code System Response
446-5 Air Shutoff Relay open The Electronic Control Module (ECM) detects an open circuit and/or a short to the +Battery in the solenoid circuit. The ECM can only detect this condition when the sourcing driver for the air shutoff solenoid is not energized. The code is logged.
446-6 Air Shutoff Relay short The ECM detects a short circuit to ground in the solenoid circuit. The ECM can only detect this condition when the sourcing driver for the air shutoff solenoid is energized. The air shutoff relays can be activated without the aid of the ECM. When the emergency stop on the instrument panel is depressed, the air shutoff relays are activated. The air shutoff timer will allow the air shutoff relays to deactivate after 2.4 seconds in order to prevent damage to the air shutoff solenoids.The ECM has the ability to stop the engine in an emergency situation by shutting off the intake air supply. The ECM activates two relays which energize the two air shutoff solenoids. The solenoids trip the air shutoff valves. The presence of a switch at each air shutoff valve informs the ECM that the air shutoff solenoids have activated. 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 relays. The ECM supplies voltage to the air shutoff relays for 2.4 seconds. The output of the relay will energize the air shutoff solenoids in order to shut down the engine.Emergency Stop Sequence - The second condition occurs when the operator initiates a remote shutdown. If the customer's emergency stop is activated, the shutdown inputs to the ECM are opened. This signals the ECM to turn on the output for the air shutoff relays. The ECM will hold the air shutoff relays active for 2.4 seconds.Overspeed Verify Feature - The third condition occurs when the overspeed verify feature is initiated with Caterpillar Electronic Technician (ET). This feature will energize the air shutoff relays when the engine speed is increased above 75 percent of the rated engine speed. The ECM supplies voltage to the air shutoff relays for 2.4 seconds during the shutdown. The overspeed verify feature can be initiated in order to test the operation of the air shutoff system.Regardless of the reason for activation, the Engine Control Switch (ECS) must be turned to the OFF position for three seconds in order to reset the ECM and the air shutoff timer. The operator must manually open the air shutoff valves in order to reset the switches at the air shutoff valves.
Illustration 1 g01949553
Typical schematic
Illustration 2 g01216447
P1 ECM connector
(P1-5) Digital return
(P1-23) Engine shutdown "C"
(P1-28) Engine shutdown "D"
(P1-55) Air shutoff is tripped.
(P1-56) Battery
Illustration 3 g01234146
Location of ECM connectors
Illustration 4 g01216448
P2 ECM connector
(P2-13) Air shutoff
Illustration 5 g01216449
Connector A
(Terminal 1) −Battery
(Terminal 15) Air shutoff
(Terminal 19) +Battery
(Terminal 21) Engine shutdown "D"
(Terminal 23) Engine shutdown "C"
(Terminal 25) Digital return
Illustration 6 g01216450
Connector B
(Terminal 9) RH air shutoff solenoid
(Terminal 11) LH air shutoff solenoid
Illustration 7 g01216451
Customer connector
(Terminal 20) Digital return
(Terminal 33) Engine shutdown "C"
(Terminal 34) Engine shutdown "D" Test Step 1. Inspect Electrical Connectors and Wiring
Turn the ECS to the OFF position.
Thoroughly inspect the ECM connectors. Inspect all of the other connectors for the circuit. Refer to Troubleshooting, "Inspecting Electrical Connectors" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Inspecting Electrical Connectors" for details.
Check the harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The connectors and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem in the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem. Test Step 2. Check for Active Diagnostic Codes
Connect Cat ET to the service tool connector.
Turn the ECS to the STOP position.
Monitor the active diagnostic code screen on Cat ET. Check the air shutoff relay for an active -5 diagnostic code. Note: Wait at least 30 seconds in order for the diagnostic code to become active.
Proceed to the "Diagnostic Overrides" screen on Cat ET. Activate the override for the air shutoff.
Monitor the active diagnostic code screen on Cat ET. Check the air shutoff relay for an active -6 diagnostic code. Note: Wait at least 30 seconds in order for the diagnostic code to become active.
Turn the ECS to the OFF position. Expected Result:No diagnostic codes