COOLER & MTG GP-HYDRAULIC OIL 2040966 - Caterpillar

Illustration 1 g00682326
Typical schematic for diagnostic enable switchThe return wire may be connected to P1-3, P1-5, or P1-18.
Illustration 2 g01153515
Pin locations on ECM connector (P1-5) AP sensor/switch common (P1-46) Input 7 (diagnostic enable)Test Step 1. Check the Electrical Connectors and the Wiring
Thoroughly inspect the J1/P1 ECM connector and the firewall bulkhead connectors. Refer to Troubleshooting, "Inspecting Electrical Connectors" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the suspect switch circuit.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and the wiring for abrasion and for pinch points from the battery to the ECM. Then, check from the keyswitch to the ECM.Refer to Illustration 2 for terminal locations for the ECM.Expected Result:All connectors are free of corrosion, of abrasion, and of pinch points.Results:
OK - Proceed to Test Step 2.
Not OK - Repair the wiring and connectors or replace the wiring or the connectors. Ensure that all of the seals are properly connected. Verify that the repair eliminates the problem.STOPTest Step 2. Use Caterpillar Electronic Technician (ET) to Check the Status of the Diagnostic Enable Switch
Connect Cat ET at the cab data link connector.
Turn the keyswitch to the ON position.
Operate the diagnostic enable switch in the ON and OFF positions.
View the "Input 7" status on the Cat ET status screen.
If the "Input 7" status indicates "None", then the "Input 7" parameter has not been programmed.Expected Result:The "Status Screen" indicates "ON" if the switch is turned on. The "Status Screen" indicates "OFF" if the switch is off.Results:
OK - The switch is operating normally. Continue troubleshooting if the original condition is not resolved.STOP
Not OK - The ECM is not reading the "Switch Status" change. Proceed to Test Step 3.Test Step 3. Check the Switch Circuit for the ECM
Illustration 3 g01118111
Pin locations on breakout T (5) AP sensor/switch common (46) Input 7 (diagnostic enable)
Turn the keyswitch to the OFF position.
Install a breakout T at the J1/P1 ECM connector.
Fabricate a jumper wire 100 mm (4 inch) long. Crimp a Deutsch pin to both ends of the wire.
Insert the jumper wire into terminal 46 Input 7 of the breakout T. Connect the other end of the jumper wire to terminal 5 AP sensor/switch common of the breakout T.
Verify that the keyswitch is in the ON position.
Alternately remove the jumper wire and then insert the jumper wire from terminal 5. At the same time, monitor the "Status Screen" on Cat ET.Expected Result:The "Switch Status" changes to "ON" with the jumper wire in place. The "Switch Status" changes to "OFF" when the jumper wire is removed.Results:
OK - The ECM is functioning properly at this time. Proceed to Test Step 4.
Not OK - The ECM is not functioning properly.Repair: Temporarily connect a test ECM. If the problem is resolved with the test ECM, install the suspect ECM. If the problem returns with the suspect ECM, replace the ECM.Verify that the repair eliminates the problem.STOPTest