KIT-SEAL 2698599 - Caterpillar

System Operation Description:This feature is only available on GMT-560 applications.Use this procedure to troubleshoot the system only when there is an active diagnostic code or when a diagnostic code can easily be activated.The fuel level sensors are OEM installed components for the vehicle. The sensors are selectable through a customer programmable parameter and the customer programmable parameter may be protected by customer passwords.The sensors read the level of fuel in the primary fuel tank and secondary fuel tank. The sensors require a +5 VDC supply from the Engine Control Module (ECM). The customer programmable parameters "Primary Fuel Tank Size" and "Secondary Fuel Tank Size" must be programmed to "25", "35", or "50" for this feature to work.
Illustration 1 g00844899
Typical circuit schematic for the fuel level sensors
The return wire may be connected to P1-3, P1-5, or P1-18.
Illustration 2 g01151126
Pin location on ECM connector
(P1-3) Sensor common
(P1-15) Primary fuel tank level
(P1-26) Secondary fuel tank level Test Step 1. Inspect Electrical Connectors and Wiring
Thoroughly inspect the J1/P1 ECM connector and the terminals for the fuel level sensors in the connectors. Refer to Troubleshooting, "Electrical Connectors-Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the fuel level sensors.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and wiring for abrasion and pinch points from the sensors to the ECM. Expected Result:All connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion or of pinch points.Results:
OK - Proceed to Test Step 2.
Not OK - 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. Clear all diagnostic codes.STOPTest Step 2. Determine the Condition that is Present
Connect Caterpillar Electronic Technician (ET) to the data link connector.
Turn the key switch to the ON position. Wait at least 15 seconds for activation of the diagnostic codes.
Monitor the "Active Diagnostic Code" screen on Cat ET for diagnostic codes that are related to the fuel level sensors. Expected Result:A short circuit diagnostic code 04 is active or an open circuit diagnostic code 03 is active.Results:
Voltage Low - A short circuit diagnostic code 04 is active at this time. Proceed to Test Step 3.
Voltage High - An open circuit diagnostic code 03 is active at this time. Proceed to Test Step 4.Test Step 3. Disconnect the Sensor in order to Create an Open Circuit
Turn the key switch to the OFF/RESET position.
Disconnect the connector of the sensor with the short circuit diagnostic code.
Turn the key switch to the ON position. Wait at least 15 seconds for activation of the diagnostic codes.
Monitor the "Active Diagnostic Code" screen on Cat ET. Expected Result:An open circuit diagnostic code 03 for the disconnected sensor is now active.Results:
OK - A short circuit diagnostic code 04