3AC-10169-0 Tohatsu PLATE

Table 1
Diagnostic Codes Table
Description Conditions which Generate this Code System Response
336-2 Incorrect ECS Switch inputs The two inputs from the ECS are in the opposite state. The code is logged. The Electronic Control Module (ECM) receives four input signals from the ECS. The input signals allow the control to determine the mode of operation. The ECS can operate in four modes: OFF, MAN/START, COOLDOWN/STOP and AUTO.When the ECS is set to the OFF position, the start/run/stop inputs to the ECM and the auto input to the ECM is open. The ECM is not powered. Engine operation will stop when the ECS is switched to this position.When the ECS is set to the AUTO position, the start/run/stop inputs to the ECM are open and the auto input to the ECM is low. The ECM is powered. If the remote start switch is closed, the engine start sequence will begin.When the ECS is set to the MAN/START position, the start/run/stop inputs to the ECM are low and the ECS in auto input to the ECM is open. The ECM will begin the engine start sequence.When the ECS is set to the COOLDOWN/STOP position, the start/run/stop inputs to the ECM are open and the ECS in auto input is open. After the engine cooldown, the ECM will shut down the engine.If the inputs from the start/run/stop input to the ECM are in opposite states, the ECM determines that one of the inputs is faulty. The ECM will not initiate the engine start sequence. The ECM generates a diagnostic code. The diagnostic code will be active until the condition is corrected. If this occurs, the engine may be cranked manually. Use the "Manual Crank Switch" which is located inside the electronic instrument panel. When the engine is shutdown, the ECS must be placed in the OFF position. This will disconnect power to the input for the keyswitch on the ECM and the ECM will power down. The status for the ECS will display "ABNORMAL DATA" until the condition is corrected.If the engine is running and the inputs from the start/run/stop input to the ECM change to opposite states, the engine will continue to run. The ECM generates a diagnostic code. The condition must be corrected before the ECM will initiate another engine start sequence.If you close the remote start switch, and the ECS is in the AUTO position, the engine will start. The status for the switch will display "ON" or "OFF". This status of the remote start switch is available on the Caterpillar Electronic Technician (ET) when the ECS is in the AUTO position.
Illustration 1 g01218372
Typical schematic
Illustration 2 g01218373
P1 ECM connector
(P1-5) Digital return
(P1-21) "Start/Run/Stop 1"
(P1-22) "Start/Run/Stop 2"
(P1-68) "ECS in Auto"
Illustration 3 g01234146
Location of ECM connectors
Illustration 4 g01218374
"Connector A"
(Terminal 18) "ECS in Auto"
(Terminal 25) Digital return
Illustration 5 g01218376
"Connector B"
(Terminal 2) "Start/Run/Stop 1"
(Terminal 3) "Start/Run/Stop 2"
Illustration 6 g01218377
Customer connector
(Terminal 20) Digital return
(Terminal 29) "Auto 2"
(Terminal 30) "Auto 1" Test Step 1. Inspect Electrical Connectors and Wiring
Remove electrical power from the ECM.
Thoroughly inspect the ECM connectors J1/P1. Inspect all of the other connectors. Refer to Troubleshooting, "Inspecting Electrical Connectors" for the proper procedure for inspecting system wiring.
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. Refer to Troubleshooting, "Inspecting Electrical Connectors" for details.
Check the harness and the wiring for abrasion and for pinch points. 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 harness and wiring are 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.Repair CompleteTest Step 2. Check the Status of the ECS on Cat ET
Turn the circuit breaker for the battery to the ON position.
Turn the circuit breaker for the mag relay of the starting motor system to the OFF position.
Turn the ECS to the STOP position.
Connect Cat ET to the service tool connector.
Observe the status for the ECS on Cat ET. Expected Result:The status for the ECS reads "STOP".Results:
OK - The status does display "STOP". The ECS is functioning correctly. Proceed to Test Step 3.
Not OK - The status does not display "STOP". Proceed to Test Step 4.Test Step 3. Check the Status of the ECS in the START Position
Turn the ECS to the START position.
Observe the status for the ECS on Cat ET. Expected Result:The status for the ECS reads "RUN".Results:
OK - The status for the ECS does display "RUN". The ECS is working correctly. Proceed to Test Step 5.
Not OK - The status for the ECS does not display "RUN". Proceed to Test Step 4.Test Step 4. Simulate the RUN Position at the ECM
Turn the ECS to the OFF position.
Disconnect ECM connector P1 from the ECM. Remove wire 998-BR(Brown) from P1-5. Insert a wire jumper into P1-5. Note: The digital return will no longer be connected to the other sensors and switches. Additional diagnostic codes will be generated from the ECM. Clear the codes after you complete this test.
Remove wire F716-WH(White) from P1-21. Insert a wire jumper into P1-21.
Remove wire F717-YL(Yellow) from P1-22. Insert a wire jumper into P1-22.
Reconnect connector P1 to ECM connector J1.
Use a wire jumper to connect the jumper wire in P1-5 to the jumper wires in P1-21 and P1-22.
Turn