BASIC ENGINE ARRANGEMENT 1N5839 - Caterpillar

Illustration 1 g00450440
Secondary Steering Intermediate Relay SchematicCID 0795 FMI 05 service code can only be recorded if the optional secondary steering system is installed. The secondary steering system must be energized in the power train electronic control module (ECM) software via the Caterpillar Electronic Technician (ET) configuration screen. CID 0795 FMI 05 service code is recorded when the power train ECM reads the current of the relay circuit as below normal (open circuit).Note: Ensure that the service code CID 0795 FMI 05 for the relay is active. Before performing this procedure, refer to table 1 in order to determine the connector contact number and the wire number that corresponds to the failed circuit.
Table 1
Relay Information    
Fault    Connector Contact No.    Wire No.    
Secondary Steering Int Relay     J1-4 (1)     728-BU    
( 1 ) Connector contact number of the power train ECM.Note: All relay return lines are joined and connect to contacts J1-7 and J2-3 (wire 975-WH) of the ECM.Note: The approximate coil resistance of the relay is 200 to 500 Ohms.
Check the resistance of the relay.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness from the suspected relay.
At the relay, measure the resistance between the two contacts of the relay connector. Expected Result: The resistance should be between 200 to 500 ohms.Results:
OK - The relay resistance is correct. Either the wire for relay signal or the relay return circuit (wire 975-WH) is open in the harness. Reconnect the relay and go to Step 2.
NOT OK - The relay is failed. Replace the relay. STOP.
Check the relay circuit for an open.
The key start switch and the disconnect switch remain in the OFF position.
Disconnect the machine harness connectors J1 and J2 from the power train ECM.
At machine harness connector J1 or J2, measure the resistance from the relay signal contact (refer to table 1) to J2-3 (return) or J1-7 (return). Expected Result: The resistance should be between 200 to 500 ohms.Results:
OK - The machine harness circuit resistance is correct. Suspect an intermittent fault. Go to Step 3.
NOT OK - Resistance is not correct. The open is in the wire for the relay signal or in wire 975-WH of the machine harness. Check continuity on each of the circuits. Repair the machine harness or replace the machine harness. STOP.
Check if the fault is still present.
Inspect the contacts and clean the contacts of the harness connectors.
Reconnect all harness connectors.
Turn the disconnect switch and the key start switch to the ON position.
Operate the machine. See if the fault reappears.
Check to see if the CID 0795 FMI 05 service code for the relay has recurred.Expected Result: The CID 0795 FMI 05 for the relay is active.Results:
YES - The fault has not been corrected. It is unlikely that the power train ECM is faulty. Perform the previous steps again. If the cause of the fault is not found, replace the power train ECM. Refer to Testing and Adjusting, "Electronic Control Module (Power Train) -