99609A 1 Mercury PLUG ASSEMBLY

Illustration 1 g01330881
Schematic diagram for the electrical power supply
Test Step 1. Inspect the Electrical Connectors and the Wiring
Turn the keyswitch to the OFF position.
Illustration 2 g01183529
Location of the P1 ECM connector (typical left side engine view)
Thoroughly inspect the J1/P1 ECM connector, the battery connections, the ground connections and the connections to the keyswitch. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 3 g01112632
P1 terminal locations for the electrical power supply
(P1-48) +Battery
(P1-52) +Battery
(P1-53) +Battery
(P1-61) −Battery
(P1-63) −Battery
(P1-65) −Battery
(P1-70) Keyswitch
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the electrical power supply.
Check the allen head screw for each of the ECM connectors for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and wiring for abrasions and for pinch points from the battery to the ECM. Also, check the harness and wiring for abrasions and for pinch points from the keyswitch to the ECM. Expected Result:All connectors, pins, and sockets are completely inserted and coupled. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The harness 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 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.STOPTest Step 2. Check the Battery Voltage at the ECM
Disconnect the J1/P1 ECM connector.
Measure the voltage between P1-52 (+Battery) and P1-63 (−Battery).
Measure the voltage between P1-48 (+Battery) and P1-61 (−Battery).
Measure the voltage between P1-53 (+Battery) and P1-65 (−Battery).
Turn the keyswitch to the ON position.
Measure the voltage between P1-70 (Keyswitch) and P1-63 (−Battery). Expected Result:The measured voltage is between 22 VDC and 27 VDC.Results:
OK - The ECM is receiving the correct voltage. Repair: If an intermittent condition is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - Battery voltage is out of range - Proceed to Test Step 4.
Not OK - Keyswitch voltage out of range - Proceed to Test Step 3.Test Step 3. Check the Voltage from the Keyswitch to the ECM
Remove electrical power from the engine ECM.
Remove the wire from the terminal R of the keyswitch.
Restore electrical power to the engine ECM.
Turn the keyswitch to the ON position.
Measure the voltage on terminal B of the keyswitch to engine ground.
Measure the voltage on terminal R of the keyswitch to engine ground.
Remove electrical power from the engine ECM. Expected Result:Voltage is present on terminal B and terminal R at the keyswitch.Results:
OK - Voltage is present on terminal B and terminal R at the keyswitch.Repair: Check continuity of wire 308-YL(Yellow) between the keyswitch and the ECM. Verify that the wire does not have a short or an open.STOP
Not OK - Voltage is not present on terminal B at the keyswitch.Repair: If voltage is not present on terminal B, repair the circuit between the +Battery and the keyswitch. Check the circuit protection for the circuit. Verify that the problem is eliminated.STOP
Not OK - Voltage is not present on terminal R at the keyswitch.Repair: If voltage is present on terminal B of the keyswitch but not present on terminal R, replace the keyswitch. Return all wiring to the original configuration. Verify that the problem is eliminated.STOPTest Step 4. Check the Condition of the Batteries
Measure the no-load battery voltage at the battery posts.
Load test the batteries. Use the 4C-4911 Battery Load Tester. Refer to Special Instruction, SEHS9249, "Use of 4C-4911 Battery Load Tester for 6, 8 and 12 Volt Lead Acid Batteries" and Special Instruction, SEHS7633, "Battery Test Procedure". Expected Result:The batteries pass the load test. The measured voltage is the minimum specification for a 24V system.Results:
OK - The batteries are OK.Repair: Check the wiring between the batteries and the ECM for an open circuit or a short circuit.Check the connectors between the batteries and the ECM for moisture and/or corrosion.Repair the wiring and/or the connectors.Verify that the repair eliminates the problem.STOP
Not OK - The battery voltage is low or the battery did not pass the load test.Repair: Recharge or replace the faulty batteries. Verify that the repair eliminates the problem.STOP