3AB-05006-0 Tohatsu FRICTION PLATE

Illustration 1 g01437340
Schematic for the electrical power supply
Test Step 1. Inspect the Electrical Connectors and Wiring
Illustration 2 g01392829
Location of the connectors for the electrical power supply
(1) J1/P1 ECM connectors
(2) Interface box
Set the engine control to the OFF/RESET position. Note: For the following steps, refer to Troubleshooting, "Inspecting Electrical Connectors".
Thoroughly inspect ECM connector (1) for damage, for corrosion, and for moisture. Also, thoroughly inspect each connection and the condition of each fuse that is located in interface box (2).
Check the allen head screw for each of the ECM connectors for the proper torque.
Illustration 3 g01392896
Terminal locations at the P1 ECM connectors for the electrical power supply
(P1-52) +Battery
(P1-53) +Battery
(P1-55) +Battery
(P1-57) +Battery
(P1-63) −Battery
(P1-65) −Battery
(P1-67) −Battery
(P1-69) −Battery
(P1-70) Keyswitch
Illustration 4 g01392868
Terminal locations at the interface box for the electrical power supply
(7) Keyswitch
(11) −Battery
(12) +Battery
(F1) Main fuse (15 Amp)
(F2) Fuse for the throttle actuator (10 Amp)
(F3) Fuse for the Air/Fuel Ratio Control (AFRC) (10 Amp)
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the electrical power supply:
Check the harness and wiring for abrasion and for pinch points from the power supply to the ECM and from the engine control to the ECM. Expected Result:All of the connectors, pins, and sockets are connected properly. The connectors and the wiring do not have corrosion, abrasion, or pinch points.Results:
OK - The components are in good condition with proper connections. Proceed to Test Step 2.
Not OK - The components are not in good condition and/or at least one connection is improper.Repair: Perform the necessary repairs and/or replace parts, if necessary. Ensure that all of the seals are properly installed. Make sure that the connectors are properly fastened. Verify that the repair has eliminated the problem.STOPTest Step 2. Check the Voltage at the Power Supply and at the ECM
Make sure that the engine will not crank during this procedure. For an engine with an electric starting motor, make sure that the battery cables are disconnected from the motor. For an engine with an air starting motor system, confirm that the pressurized air supply is turned off. Ensure that the air pressure is released from the system. Note: If a power supply is used instead of batteries, the minimum voltage for the power supply is 22 VDC at 20 amperes. Troubleshoot the power supply if the voltage is less than 22 VDC or more than 29 VDC.
Measure the voltage at the terminals for the power supply. Record the voltage.
Insert two 7X-1710 Multimeter Probes into the harness side of the P1 ECM connector. Insert the first probe into terminal P1-52. Insert the second probe into terminal P1-63. Connect a multimeter to the probes.
Measure the power supply voltage at the P1 connector. During the measurement, wiggle the harness in order to check for an intermittent problem. Be sure to wiggle the harness near each of the connections. Expected Result:The voltage that is measured at the terminals for the power supply is at least 22 VDC. The voltage that is measured at the P1 ECM connector is within 1 VDC of the voltage that was measured at the terminals for the power supply. The voltage measurements are constant.Results:
OK - The ECM is receiving the correct voltage at the P1 ECM connector.Repair: Remove the probes from the P1 ECM connector.Proceed to Test Step 3.
Not OK - The ECM is not receiving the correct voltage at the P1 ECM connector.Repair: Perform the following procedure:
Remove the probes from the P1 ECM connector.
Refer to the appropriate schematic. Use a voltmeter to check the wiring. Locate the source of the voltage drop.
Perform the necessary repairs. STOPTest Step 3. Check for the Proper Operation of the Engine Control
Make sure that the engine will not crank during this procedure. For an engine with an electric starting motor, ensure that the battery cables are disconnected from the motor. For an engine with an air starting motor system, confirm that the pressurized air supply is OFF. Make sure that the air pressure is released from the system.
Establish communication between Caterpillar Electronic Technician (ET) and the ECM. Note: An E225 Engine Overcrank and/or an E233 Low Engine Pre-Lube Pressure may be generated during this test step. After you have completed this test step, clear the events from the "Logged Events" screen of Cat ET.
Observe the "Active Diagnostic" screen on Cat ET and set the engine control to the COOLDOWN/STOP position, the START position, and the AUTO position. Look for an active 336-2 diagnostic code. Repeat this step several times. Expected Result:A 336-2 diagnostic code was not activated when the engine control was set to the COOLDOWN/STOP position, the START position, and the AUTO position.Results:
OK - A 336-2 diagnostic code was not activated.Repair: The inputs from the engine control are correct. There may be an intermittent problem in the harness or in a connector. If an intermittent problem is suspected, refer to Troubleshooting, "Inspecting Electrical Connectors" for troubleshooting information.STOP
Not OK - A 336-2 diagnostic code was activated. The ECM has detected a problem with the input signals from the engine control. Proceed to Test Step 4.Test Step 4. Check the Circuit of the Engine Control
Make sure that the engine will not crank during this procedure. For an engine with an electric starting motor, make sure that the battery cables are disconnected from the motor. For an engine with an air starting