56374 Mercury NUT 40

Illustration 1 g00897107
Test Step 1. Check for Connector Damage.
Turn the circuit breaker for the engine to the OFF position.
Turn the keyswitch to the OFF position.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors. Refer to the diagnostic functional test 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 of 6.0 N m (55 lb in).
Check the customer connector (allen head screw) for the proper torque of 2.25 0.25 N m (20 2 lb in).
Check the harness and the wiring for abrasion and for pinch points.Expected Result:The connectors and wiring should be free of the following problems: damage, corrosion, abrasion and incorrect attachment.Results:
OK - The connectors and wiring are okay. Proceed to test step 2.
Not OK - The connectors and/or wiring are not okay.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Verify that the system is operating correctly. Stop.Test Step 2. Check the Ether Canister.
Remove the ether canister from the ether solenoid. Determine if the canister contains any ether. Ether can not be injected if the canister is empty.Expected Result:The ether canister should not be empty.Results:
OK - The ether canister is not empty. Proceed to test step 3.
Not OK - The ether canister is empty.Repair: Replace the empty ether canister with a full ether canister. Stop.Test Step 3. Check for "ACTIVE" Diagnostics on the Caterpillar Electronic Technician (ET).
Connect the Cat ET to the cab service tool connector J42. Start the Cat ET.
Turn the circuit breaker for the engine to the ON position.
Turn the keyswitch to the ON position.
Determine if CID-FMI 545-05, 545-06, 546-05 or 546-06 is active or logged.
Toggle the starting aid switch. Observe the parameter for the ether switch on the Cat ET.Expected Result:The parameter for the ether switch should display "ON" while the starting aid switch is toggled. The parameter for the ether switch should display "OFF" when the switch is released.Results:
OK - Active Code - The parameter for the starting aid switch displays "ON" while the starting aid switch is toggled. The parameter for the starting aid switch displays "OFF" when the starting aid switch is released. Active Diagnostics are displayed. Proceed to test step 4.
OK - Logged Code - The parameter for the starting aid switch displays "ON" while the starting aid switch is toggled. The parameter for the starting aid switch displays "OFF" when the starting aid switch is released. Logged Diagnostics are displayed. Check for an intermittent short or for an open in the wiring or in the connectors.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Verify that the system is operating correctly. Replace the ether canister on the ether solenoid. Stop.
Not OK - The parameter for the starting aid switch does not display "ON" while the starting aid switch is toggled. The parameter for the starting aid switch does not display "OFF" when the starting aid switch is released. No active codes or logged codes are present. The starting aid switch is not functioning correctly. Proceed to test step 15.Test Step 4. Check the Voltage from the Ether Start Relay.
Turn the keyswitch to the OFF position.
Connect a voltmeter between wire 310-PU on terminal 87 of the ether start relay and ground.
Turn the keyswitch to the ON position.
Select the "Diagnostic Tests" on the Cat ET.
Select the "Override Parameters" screen on the Cat ET.
Do not allow the Ether Injection System to be on for more than two minutes. Damage to the Ether Solenoid may occur.
Activate the ether override and observe the voltmeter while ether injection is activated. Disable the ether override.Expected Result:The voltage at the ether start relay should measure 24 3 VDC during the first two seconds of injection. The voltage then decreases to 3 1 VDC for the remainder of the injection duration.Results:
OK - The voltage measured approximately 24 3 VDC for the first two seconds. The voltage then decreased to approximately 3 1 VDC for the remainder of injection duration. Proceed to test step 5.
Not OK - 24 VDC - The voltage does not measure 24 3 VDC. Proceed to test step 6.
Not OK - 3 VDC - The voltage does not decrease to 3 1 VDC for the remainder of the injection duration. Proceed to test step 9.Test Step 5. Check the Voltage at the Ether Solenoid.
Turn the keyswitch to the OFF position.
Disconnect the ether solenoid connector at the solenoid.
Connect a voltmeter to pin 1 and pin 2 of the ether solenoid connector.
Turn the keyswitch to the ON position.
Do not allow the Ether Injection System to be on for more than two minutes. Damage to the Ether Solenoid may occur.
Activate the ether override and observe the voltmeter while ether injection is activated. Disable the ether override.
Reconnect all connectors.Expected Result:The voltage at the ether solenoid should measure 24 3 VDC during the first two seconds of injection. The voltage at the ether solenoid should decrease to 3 1 VDC after the first two seconds of injection.Results:
OK - The voltage measured approximately 24 3 VDC for the first two seconds of injection. The voltage then decreases to about 3 1 VDC for the remainder of injection.Repair: If ether is not being injected, replace the ether solenoid. Verify that the system is operating correctly. Replace the ether canister on the ether solenoid. Stop.
Not OK - 24 VDC - The voltage does not measure 24 3 VDC for the first two seconds of injection.Repair: Inspect the wiring and connectors between the ether start relay and the connectors at the ether solenoids. Repair the connectors or wiring and/or replace the connectors or wiring. Stop.