5034126 JOHNSON BOLT

Note: This diagnostic code represents an event. This diagnostic code does not represent an electronic system fault.The Engine Control Module (ECM) detects the following conditions:
The signal voltage from the "2 Wire Float" sensor is between 2.5 V and 3.15 V.
The reading for the coolant level sensor has been low for more than ten seconds.
The ignition key switch is in the ON position or the engine has been running for more than 30 seconds.
"Coolant Level Sensor" must be programmed to "4-pin", "2-pin switch", or "2-wire float sensor".System Response:If "Engine Monitoring" is programmed to "", the check engine lamp will flash and the warning lamp will illuminate continuously.If "Engine Monitoring" is programmed to "DERATE" or "SHUTDOWN", the check engine lamp and the warning lamp will flash.This diagnostic code requires a customer password in order to be cleared."DIAG" will be displayed next to "Engine Coolant Level" on the status screen.Possible Performance Effect:If "Engine Monitoring" is programmed to "DERATE" or "SHUTDOWN", the vehicle speed is limited to a maximum of 72 km/h (45 mph), and the power is limited. The engine will shut down if conditions exist for a long enough period in the SHUTDOWN mode.Troubleshooting:"2-Pin Switch"GMT -560 applications can use a "2-pin switch" in order to monitor coolant level.To use a "2-pin switch", the parameter "Manufacturer/Model" must be programmed to "GMT-560" and the parameter "Coolant Level Sensor" must be programmed to "2-pin switch". The diagnostic fault codes for the coolant level sensors are disabled when the "Coolant Level Sensor" parameter is programmed to "2-pin switch". The switch is connected to P1/J1-49 ( coolant level switch) and to P1/J1-5 (AP sensor/switch sensor common). If the coolant level is normal, the switch should be closed and P1/J1-49 connected to ground. The warning lamp will be illuminated via the J1939 data link when the coolant is low. Test Step 1. Check the Level of the CoolantVisually check the level of the coolant. Ensure that the coolant level switch is fully immersed in the coolant.Expected Result:The coolant is at the proper level.Results:
OK - Proceed to Test Step 2.
Not OK - Repair: Fill the cooling system with the proper coolant to the correct level. For further information, refer to the Operations and Maintenance Manual.STOPTest Step 2. Inspect Electrical Connectors and Wiring
Thoroughly inspect the following connectors:
J1/P1 ECM vehicle harness connector
Harness for the connector to the coolant level switch
Connector terminals for the switchRefer 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 appropriate diagnostic code.
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 appropriate sensor back 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 4.
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.STOPTest Step 3. Determine the Type of Coolant Level Switch
Determine the type of coolant level switch that is used. Expected Result:A "4-Pin", "2-Pin Switch", or a "2-Wire Float" is used.Results:
If a "4-Pin" or a "2-Wire Float" is used - Repair: Refer to Troubleshooting, "Coolant Level Sensor Circuit - Test".STOP
"2-Pin Switch" is used - Proceed to Test Step 4.Test Step 4. Check the Coolant Level Switch
Connect Caterpillar Electronic Technician (ET) to the data link connector.
Remove the connector to the coolant level switch.
Turn the ignition key switch to the ON position. Monitor the active diagnostic code screen.
Short the terminals on the connector to the coolant level switch. Expected Result:The "Low Coolant Level Warning" code becomes inactive when the terminals are shorted.Results:
Yes - There is a problem with the coolant level switch.Repair: Replace the coolant level switch.Ensure that the repair eliminates the problem.STOP
No - Repair: Reconnect the connector for the coolant level switch.Proceed to Test Step 5.Test Step 5. Check the Harness for the Coolant Level Switch
Turn the ignition key switch to the OFF/RESET position.
Insert a jumper between terminal J1-49 and terminal J1-5.
Turn the ignition key switch to the ON position. Monitor the active diagnostic code screen. Expected Result:The "Low Coolant Level Warning" event code becomes inactive when the terminals are shorted.Results:
Yes - The problem is in the harness wiring.Repair: Repair the wiring or replace the wiring, as required.STOP
No - The problem is on the ECM side.Repair: Temporarily connect a test ECM. Ensure that the parameters for "Engine Monitoring" and "Coolant Level Sensor" are programmed to match the old ECM. If the problem is resolved with the test ECM, reconnect the suspect ECM. If the problem returns with the suspect ECM, replace the ECM.STOP