HOSE 3633892 - Caterpillar

MID 87 - Chassis ECMCID 379 - Machine Auto Lube Pressure SensorFMI 8 - Abnormal Frequency, Pulse Width, or Period
Illustration 1 g02445118
Machine "Auto Lube" pressure sensor circuit
This diagnostic code indicates that the "Chassis ECM" detects the machine "Auto Lube" pressure sensor signal is abnormal. The signal may be abnormal in the following:
Frequency
Pulse width
Pulse periodThe following can cause this code:
Loose mechanical devices
Intermittent ground
Sensor failure
Poor connections
ECM failureNote: The following test procedure may create other diagnostic codes. Ignore these created codes and clear these created codes after the original diagnostic code has been corrected. Ensure diagnostic code CID 379 FMI 8 is active before performing this procedure.Note: Use a calibrated digital multimeter for this procedure.Test Step 1. CHECK FOR LOOSE DEVICES
Perform an inspection of all involved mechanical devices.
Visually inspect for signs of loose devices.
Attempt to wiggle the devices.Expected Result:All the devices are secure.Results:
OK - All the devices are secure. Proceed to Test Step 2.
NOT OK - All the devices are not secure.Repair: Secure the loose deviceSTOPTest Step 2. CHECK THE SENSOR
Turn on the disconnect switch and the key switch.
Disconnect the sensor from the harness while observing the diagnostic code status.Expected Result:CID 379 FMI 8 remains active and the FMI does not change.Results:
OK - CID 379 FMI 8 remains active and the FMI does not change. Proceed to Test Step 4.
NOT OK - CID 379 FMI 8 is not active or the FMI changes. The sensor has failed.Repair: Replace the sensorSTOPTest Step 3. CHECK FOR GOOD GROUND
Reconnect the sensor.
Turn off the key switch and the disconnect switch.
Remove the 7X-1710 Multimeter Probe from the voltage supply wire (contact A).
At the back of the harness connector for the sensor, insert a 7X-1710 Multimeter Probe along the ground wire contact B.
Measure the resistance from contact B to frame ground.Expected Result:The resistance is less than 5 ohms.Results:
OK - The resistance is less than 5 ohms. Proceed to Test Step 4.
NOT OK - The resistance is more than 5 ohms.Repair: Repair or replace the harnessSTOPTest Step 4. CHECK CONNECTIONSThe key switch and the disconnect switch remain in the off position.
Inspect the harness.Clean the harness connector contacts.Inspect the harness connector contacts for corrosion or damage.Inspect the wire insulation for damage caused by heat, corrosion, or chafing.
Perform a 45 N (10 lb) pull test on each circuit wire.
Reconnect all harness connectors.Verify that the connectors are fully seated and the clips are fastened.
Check for intermittent problems. Use Cat® Electronic Technician (Cat® ET) to perform a wiggle test on the harness.
Turn on the disconnect switch and the key switch.
Operate the machine.
Check CID 379 FMI 8 status.Expected Result:CID 379 FMI 8 is not active.Results:
OK - CID 379 FMI 8 is not active.Repair: The initial diagnostic code was probably caused by a poor connection at one of the connectors that was checked.Resume normal operationSTOP
NOT OK - CID 379 FMI 8 is active intermittently. There is a poor harness connection.Repair: Repair or replace the harness.STOP
NOT OK - CID 379 FMI 8 is active continuously.Repair: Exit this procedure and perform this procedure again. Contact