865344A01 Mercruiser CLUTCH ASSEMBLY

Table 1
Diagnostic Codes Table    
CDL Code and Description     Conditions which Generate the Code     System Response    
1076-5 Engine Cooling Fan Bypass Solenoid open circuit     The Electronic Control Module (ECM) detects an open circuit and/or a short to the +Battery in the cooling fan bypass solenoid.     The ECM sends minimum current to the cooling fan bypass solenoid. The code is logged.    
1076-6 Engine Cooling Fan Bypass Solenoid short to ground     The ECM detects a short circuit to ground in the cooling fan bypass solenoid.    
Illustration 1 g02340837
Location of the cooling fan bypass solenoid (1) Control Manifold Gp (2) Cooling fan bypass solenoidThe cooling fan bypass solenoid is used in areas with cold ambient temperatures. Under normal operating circumstances, the main cooling fan never turns off. The main cooling fan continues to operate at a minimum speed regardless of need. When the cooling fan bypass solenoid is activated, hydraulic flow to the fan motor will be bypassed. The result is no fan speed or slow fan speeds.The following conditions must be met in order for the cooling fan bypass solenoid to activate.
The temperature of the hydraulic oil must be between 50 °C (122 °F) and 100 °C (212 °F).
The intake manifold air temperature must be less than a map-dependent value that is based on engine rpm.
The coolant temperature must be below 88 °C (190 °F).
The engine speed must be between 500 rpm and 1500 rpm.Note: The ECM will only detect an open in the circuit if the cooling fan bypass solenoid is not activated. The ECM will only detect a short in the circuit if the cooling fan bypass solenoid has been activated.
Illustration 2 g01251396
Schematic for the cooling fan bypass solenoidTest Step 1. Inspect the Electrical Connectors and the Wiring
Turn the keyswitch to the OFF position.
Illustration 3 g01415758
Location of ECM connectors
Thoroughly inspect the J1/P1 ECM connectors. Also, thoroughly inspect all of the other connectors for the circuit. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 4 g01416322
Terminal locations at the P1 ECM connector for the cooling fan bypass solenoid (P1-18) Digital return (P1-19) Cooling fan bypass solenoid
Illustration 5 g01155187
Terminal locations at the solenoid connector for the cooling fan bypass solenoid (Terminal 1) Power to the cooling fan bypass solenoid (Terminal 2) Digital return
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 allen head screw for each of the ECM connectors for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points.Expected Result:All connectors, pins, and sockets are coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The harness and connectors appear to be 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 coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Check for Active Diagnostic Codes
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the keyswitch to the ON position.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Select diagnostic tests from Cat ET.
Select the "Override Parameters" screen on Cat ET.
Activate the override for the cooling fan bypass solenoid.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 30 seconds in order for the diagnostic code to become active.
Disable the override for the cooling fan bypass solenoid.
Determine if the problem is related to an open circuit diagnostic code -5 or a short circuit diagnostic code -6.Expected Result:No diagnostic codes are active.Results:
OK - No diagnostic codes are active.Repair: The problem may have been related to a faulty connection in the harness. Carefully inspect the connectors and wiring. Refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - A short circuit diagnostic code -6 is active at this time. Proceed to Test Step 3.
Not OK - An open circuit diagnostic code -5 is active at this time. Proceed to Test Step 4.Test Step 3. Create an Open Circuit at the Harness Connector for the Cooling Fan Bypass
Turn the keyswitch to the OFF position.
Disconnect the connector for the cooling fan bypass solenoid.
Turn the keyswitch to the ON position.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Select diagnostic tests from Cat ET.
Select the "Override Parameters" screen on Cat ET.
Activate the override for the cooling fan bypass solenoid.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 30 seconds in order for the diagnostic code to become active.
Disable the override for the cooling fan bypass solenoid.Expected Result:An open circuit diagnostic code -5 is now active for the cooling fan bypass solenoid.Results:
OK - A short circuit diagnostic code -6 was active before disconnecting the connector. An open circuit diagnostic code -5 became active after disconnecting the connector.Repair: Temporarily connect a new cooling fan bypass solenoid to the harness, but do not install the new cooling fan by