CABLE AS 7E8661 - Caterpillar

Machine ECM
The following is a list of Diagnostic Trouble Codes (DTCs) that are associated with the condition switch (two wire) of the machine.
Table 1
Machine ECM (MID 39)
DTC Code Description System Response
1195-4 Hydraulic Filter Bypass Switch: Voltage Below Normal There is no direct impact. If ignored, could lead to false trips of 1267-2 event for "Hydraulic Oil Filter Plugged" Possible causes for an FMI 4 diagnostic code are:
The signal is permanently grounded.
The switch has failed.
Can occur on power-up when engine is not running. Here, the switch is expected to be in the resting 'not bypassing' state. The fault occurs if it is observed in the 'bypassing' state for 2 seconds.
The ECM has failed. This condition is unlikely.
Illustration 1 g03748775
Schematic of the condition switch connection
Note: The diagram above is a simplified schematic of the connections for the condition switch. The schematic is electrically correct. However, not all of the possible harness connectors are shown. Refer to the latest revision of the electrical schematic for the specific machine being serviced for the complete schematic.
Table 2
Status of the Switch
MODE Pressure J2-44
wire N787-BU(Blue)
Filtering Low Closed(1)
Bypass High Open(1)
(1) Continuity when the switch is closed, is less than 5 ohms. Continuity when the switch is open, is greater than 5000 ohms.Diagnostic Trouble Code Procedure
Note: Prior to beginning this procedure, inspect the harness connectors that are involved in this circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, secure, and in good condition. Check the wiring for pinch points or abrasions. Look for and repair areas that indicate wires are exposed. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing a troubleshooting procedure.
Table 3
Troubleshooting Test Steps Values Results
1. Identify The Active DTC Code Associated With The Condition Switch
Code present. FMI 4 diagnostic code, proceed to Test Step 2.
Begin Process for FMI 4 Troubleshooting HERE
2. Check The Ground Circuit For An Open
A. Turn the disconnect switch and the keyswitch to the OFF position.
B. Disconnect the switch from the machine harness.
C. Measure the resistance between frame ground and - battery at the connector for the switch.
The resistance should be less than 5 ohms. OK - The resistance is less than 5 ohms.
Proceed to Test Step 3.
NOT OK - The resistance is greater than 5 ohms.
Repair:The return circuit is open in the machine harness. Repair the machine harness or replace the machine harness.
Proceed to Test Step 5.
3. Check The Switch
A. Check for continuity between contact 1 and contact 2 of the switch.
B. Check for continuity between contact 1 and contact 2 of the switch.
The continuity check agrees with Table 1. OK - The continuity check agrees.
Proceed to Test Step 4.
NOT OK - The continuity check does not agree. The switch has failed.
Repair: Replace the switch. Verify that the new switch corrects the diagnostic code.
Proceed to Test Step 4.
4. Check The Signal Circuits In The Harness For An Open
A. Reconnect the switch to the machine