3BJQ60100-0 Tohatsu ASSEMBLY

Illustration 1 g01534716
Schematic for the electric starting system
Illustration 2 g01325950
Schematic for the air start system
Test Step 1. Inspect the Electrical Connectors and Wiring
Remove the electrical power from the engine. Note: For the following steps, refer to Troubleshooting, "Electrical Connectors - Inspect".
Thoroughly inspect the following connectors and the wiring harnesses for the connectors:
J2/P2 connectors
J7/P7 connectors
Check the torque of the allen head screw for the ECM connectors.
Illustration 3 g01055043
Harness side of the P2 connector
(P2-10) Start command
(P2-20) Return for the start command
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit for the starting motor relay.
Check the harness and wiring for abrasion and for pinch points from the starter motor relay to the ECM. Expected Result:All 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, when possible. Replace parts, if necessary.STOPTest Step 2. Check for Diagnostic Codes
Connect Cat ET to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".
Switch the 35 amp circuit breaker ON. Set the engine control to the STOP mode. Note: The 444-5 diagnostic code can only be detected when the output for the start command is off. The output is normally off when the engine control is in the STOP mode or when the crank terminate relay is energized.
Wait for 30 seconds and use Cat ET to check for an active 444-5 diagnostic code. If there is an active 444-5 diagnostic code, proceed to the “Results” for this Test Step. Otherwise, continue this procedure.
Use Cat ET to check the logged diagnostic codes. If there is a logged 444-6 diagnostic code, clear the code.
To prevent the engine from starting, shut the gas supply OFF. Note: The 444-6 diagnostic code can only be detected when the output for the start command is ON. The output is normally ON when the engine control is set from the STOP mode to the START mode. The output remains ON until the crank terminate relay is energized.
Set the engine control to the START mode for at least six seconds. Then set the engine control to the STOP mode.
Use Cat ET to look for a logged 444-6 diagnostic code again. Expected Result:When the engine control was in the STOP mode, there was no active 444-5 diagnostic code.After the engine was cranked, there was no logged 444-6 diagnostic code.Results:
OK - No diagnostic codes were activated. The output for the start command seems to be OK at this time. The initial diagnostic code was probably caused by a poor electrical connection.Repair: If there is an intermittent problem that is causing the codes to be logged, refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK (444-5 diagnostic code) - A 444-5 diagnostic code was activated. This can be caused by an actual open circuit or by a short circuit to the +Battery side. If the engine is equipped with an air start system, proceed to Test Step 3. If the engine is equipped with an electric starting system, proceed to Test Step 9.
Not OK (444-6 diagnostic code) - After the engine was cranked, a 444-6 diagnostic code was activated. If the engine is equipped with an air start system, proceed to Test Step 7. If the engine is equipped with an electric starting system, proceed to Test Step 10.Test Step 3. Check for a Short Circuit to the +Battery Side
Gaseous fuel is present. Personal Injury or Death can result from an open flame or spark igniting the gaseous fuel causing an explosion and/or fire. Always use a gas detector to determine the presence of gaseous fuel when maintaining and servicing. Contact you local gas provider immediately for assistance in the event of a leak.
Note: Open sparks can be generated during this test.
Make sure that no combustible gas is present in the surrounding atmosphere.
Ensure that the engine control is in the STOP mode.
Disconnect the connector from the air start relay. Then reconnect the connector. Listen for an audible click from the relay. If the ambient noise is too loud, touch the air start relay when the relay is reconnected in order to feel the vibration. The relay will vibrate when the relay is de-energized and energized.Expected Result:There is no audible click and/or vibration when the air start relay is disconnected and reconnected. The relay is not energized when the engine control is in the STOP mode.Results:
OK - There is no audible click and/or vibration when the air start relay is disconnected and connected. There is no short circuit to the +Battery side. There is an open circuit. Proceed to Test Step 4.
Not OK - There is an audible click and/or vibration when the air start relay is disconnected and connected. The relay is receiving power when the engine control is in the STOP mode. Proceed to Test Step 6.Test Step 4. Create a Short Circuit in order to Check for an Open Circuit
Set the engine control to the OFF/RESET mode. Switch the 35 amp circuit breaker OFF.
Disconnect the harness connector from the air start relay.
Install a jumper wire into the two terminals of the harness connector for the air start relay.
Switch the 35 amp circuit breaker ON. Set the engine control to the STOP mode.
Wait for 30 seconds and use the "Active Diagnostic" screen of Cat ET to look for a 444-5 diagnostic code. Expected Result:A 444-5 diagnostic code was not activated when the jumper wire was installed.Results:
OK - A 444-5 diagnostic code was not activated when the jumper wire was installed. The