865441A02 Mercruiser COVER ASSEMBLY, Back

Illustration 1 g01502177
Typical circuit for the indicator lamps
Illustration 2 g01502252
A typical view of the P1 connector (harness side) pin locations.
(1) Ground
(2) Ground
(3) Ground
(9) Ground
(10) Ground
(7) Battery (+)
(8) Battery (+)
(15) Battery (+)
(16) Battery (+)
(40) Keyswitch
(59) Warning lamp
(60) Stop lamp
(61) PTO mode lamp
(62) Low oil pressure lamp
(63) Wait-to-start lamp Test Step 1. Inspect Electrical Connectors and Wiring
Remove the electrical power from the ECM.
Thoroughly inspect the P1 connector, and the lamp connections. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the indicator lamps.
Check the allen head screw on each ECM connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Check the harness for abrasions and for pinch points from the battery to the ECM. 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 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 the harness and/or replace the connectors or the harness. Ensure that all of the seals are correctly in place and ensure that the connectors are completely coupled.If necessary, use the electronic service tool to perform a "Wiggle Test".Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.STOPTest Step 2. Check for Normal Operation of the Suspect Lamp
Restore the electrical power to the ECM and monitor the indicator lamps.
The diagnostic lamps will illuminate for a minimum of two seconds after the power is returned to the ECM. The lamps will then turn off.
Remove the electrical power from the ECM. Expected Result:The suspect lamp illuminates and the lamp turns off per the above description.Results:
OK - The suspect lamp illuminates and the lamp turns off per the above description.Repair: The diagnostic lamps appear to operating correctly at this time. There may be an intermittent electrical problem in the harness or in a connector. If an intermittent problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - The suspect lamp does not illuminate or the suspect lamp does not turn off per the above description. Proceed to Test Step 3.Test Step 3. Measure the Voltage at the Lamp Socket
Restore the electrical power to the ECM.
Use the electronic service tool to select the "override" function in order to switch individual lamps ON and OFF. Note: The "Override" function is contained in the "Diagnostics" menu of the electronic service tool.
Measure the voltage at the suspect lamp socket. Expected Result:The voltage is between 18.0 VDC and 24.0 VDC.Results:
OK - The voltage is between 18.0 VDC and 24.0 VDC.Repair: Replace the bulb. Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.STOP
Not OK - The voltage is not between 18.0 VDC and 24.0 VDC. Proceed to Test Step 4.Test Step 4. Test the Lamp Circuit
Remove the electrical power from the ECM.
Disconnect the P1 connector.
Temporarily disconnect the wire from the P1 connector for the suspect lamp.
Temporarily disconnect the wire from one of the Battery+ connections on the P1 ECM connector.
Fabricate the jumper wire with a suitable pin for the P1 connector.
Install one end of the jumper wire into the P1 connector socket for the suspect lamp. Connect a test lamp between the Battery+ wire and the jumper wire.
Reinstall the P1 connector to the ECM.
Restore the electrical power to the ECM. Use the electronic service tool to select the override function in order to switch individual lamps ON and OFF. Note: The "Override" function is contained in the "Diagnostics" menu of the electronic service tool.Expected Result:The test lamp will illuminate.Results:
OK - The test lamp illuminated. The ECM is operating correctly.Repair: There is a fault in the wiring or the lamp. Repair the wiring or the lamp, as required.Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.STOP
Not OK - The test lamp did not illuminate.Repair: Perform the following procedure:
Make sure that the latest flash file for the application is installed in the ECM. Refer to Troubleshooting, "Flash Programming".
Use the electronic service tool to check for active diagnostic codes.
If a diagnostic code is still active, contact the technical communicator at a Caterpillar dealer. Note: This consultation can greatly reduce the repair time.
If necessary, install a test ECM. Refer to Troubleshooting, "Replacing the ECM".
Use the electronic service tool to verify that the fault is eliminated.
If the fault is eliminated with the test ECM, reconnect the suspect ECM. Verify that the active diagnostic code returns.
If the active diagnostic code returns with the suspect ECM, replace the ECM. STOP