0378101 JOHNSON SPARK PLUG,Champion j4j

Illustration 1 g01132350
Coolant level sensor (1) Sensor (2) Brass rod (3) Plastic coverCoolant level sensor (1) contains no moving parts. The sensor detects variations in capacitance. The sensor's probe contains a brass rod (2) that is covered with plastic (3). The brass rod is one plate of a capacitor. The coolant is the other plate of the capacitor. The plastic cover is the dielectric between the plates of the capacitor.When the probe is immersed in coolant, the sensor senses a particular capacitance. The sensor responds by creating a short circuit between the signal wire and the ground wire.When the probe is not immersed in coolant, the capacitance value changes. The change in the capacitance value is detected by the sensor's electronic circuits. The Electronic Control Module (ECM) detects the voltage and the ECM activates one of the following event codes:
E057 Low Engine Coolant Level Derate
E058 Low Engine Coolant Level Shutdown
E059 Low Engine Coolant Level WarningAn event code is probably caused by a low coolant level. The next likely cause is a problem with a wiring harness or with the sensor. The least likely cause is a problem with the ECM.
Illustration 2 g01288782
Schematic for the coolant level sensor
Illustration 3 g01288698
P1 terminal that is associated with the coolant level sensor (P1-47) Coolant level
Illustration 4 g01094844
Sensor connector
Pressurized System: Hot coolant can cause serious burns. To open the cooling system filler cap, stop the engine and wait until the cooling system components are cool. Loosen the cooling system pressure cap slowly in order to relieve the pressure.
Test Step 1. Inspect the Electrical Connectors and the Wiring
Remove the electrical power from the ECM.
Thoroughly inspect ECM connector J1/P1. Inspect the connectors for the coolant level sensor. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit for the coolant level sensor.
Check the allen head screw on each ECM connector for the proper torque. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The connectors and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem with the connectors and/or the wiring.Repair: 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.Verify that the repair eliminates the problem.STOPTest Step 2. Check the Supply Voltage at the Sensor Connector
Disconnect the coolant level sensor.
Restore the electrical power to the ECM.
Measure the voltage between terminals A (+24 VDC) and B (Return) at the harness connector for the coolant level sensor.
Remove the electrical power from the ECM.Expected Result:The voltage measurement is 24.0 2.0 VDC.Results:
OK - The voltage measurement is 24.0 2.0 VDC. The supply voltage is reaching the sensor. Proceed to Test Step 3.Test Step 3. Check the Coolant Level
Pressurized System: Hot coolant can cause serious burns. To open the cooling system filler cap, stop the engine and wait until the cooling system components are cool. Loosen the cooling system pressure cap slowly in order to relieve the pressure.
Remove the electrical power from the ECM.
After allowing the engine to cool, check the coolant level. Refer to the Operation and Maintenance Manual.Expected Result:The coolant is at the proper level.Results:
OK - The coolant is at the proper level. Proceed to Test Step 4.
Not OK - The coolant level is low.Repair: Add coolant according to the procedure in the Operation and Maintenance Manual.Verify that the repair eliminates the problem. Identify the source of the coolant leak and fix the problem.STOPTest Step 4. Disconnect the Coolant Level Sensor and Monitor the Status of "Coolant Level"
Connect the Caterpillar Electronic Technician (ET) to the service tool connector. Refer to electronic troubleshooting Troubleshooting, "Electronic Service Tools".
Disconnect the connector for the coolant level sensor.
Restore the electrical power to the ECM.
Monitor the status of "Coolant Level" on Cat ET.
Remove the electrical power from the ECM.Expected Result:The status changes from "OK" to "Low" when the sensor is disconnected.Results:
OK - The status is "Low" when the sensor is disconnected. Proceed to Test Step 5.
Not OK - The status is "OK" when the sensor is disconnected. Proceed to Test Step 6.Test Step 5. Short the Harness and Monitor the Status of "Coolant Level"
Restore the electrical power to the ECM and monitor the status of "Coolant Level" on Cat ET.
Install a jumper wire between terminals B (Return) and C (Signal) on the harness connector for the coolant level sensor.
Monitor the status of "Coolant Level" on Cat ET while the jumper wire is installed.
Remove the jumper wire.
Remove the electrical power from the ECM.Expected Result:The status changes from "Low" to "OK" when the jumper wire is installed.Results:
OK - The status changes from "Low" to "OK" when the jumper wire is installed. The ECM and the wiring to the coolant level sensor are OK. There may be a problem with the coolant level sensor.Repair: Perform the following procedure:
Pressurized System: Hot coolant can cause serious burns. To open the co