HEATER 240 VOLT, 3 KILOWATT 5L7806 - Caterpillar

As instructed in the "Power Train Electrical System Service Shutdown" procedure that was performed at the beginning of this procedure, use the High Voltage Cage meter to measure voltage between the "P" and the "N" DC Bus connections on the phase module. Verify that there is less than 50.0 VDC on the DC Bus. Once voltage level is verified, continue to the next step.Note: In addition to the temperature sensor circuits, the phase module harness connector contains the fiber optic control circuits. Do not use tools to disconnect or reconnect the phase module harness connector. When disconnecting the connector by hand, turn the locking collar counterclockwise. Carefully pull the harness straight away from the mating connector. When reconnecting, line up the connector with the guide pins and gently push straight into the mating connector. Turn the locking collar clockwise to hold the connector in place.
At the Chopper phase module, carefully disconnect the low phase module connector. Examine the pins, the sockets, and the fiber optic contacts. Ensure that all of the pins and sockets are secured in the connector. Ensure that all of the circuit contacts that are used in the connector are clean and the contacts are in good condition.
Illustration 5 g01830794
Phase module connector (13) Temperature sensor positive circuit - "F" (14) Temperature sensor negative circuit - "G"
At the phase module connector, use a multimeter to measure the resistance between the temperature sensor positive contact "F" and the temperature sensor negative contact "G". Expected Result:The resistance measurement between the temperature sensor contacts at the phase module connector is between the range of 500 ohms and 2000 ohms.Results:
YES - The resistance measurement between the temperature sensor positive and negative circuits is within the range of between 500 ohms and 2000 ohms. This resistance range is what the ECM will consider as acceptable. The resistance measurement is indicating that the temperature sensor in the phase module is good. Proceed to the Test Step 4.
NO - The resistance measurement between the temperature sensor contacts at the phase module connector is not within the range of 500 ohms and 2000 ohms. The resistance measurement is indicating that the temperature sensor inside of the Chopper phase module has failed.Repair: The phase module temperature sensors are not serviceable. In order to replace the temperature sensor, the phase module must be replaced. Replace the phase module that contains the faulty temperature sensor. Refer to Power Train Disassembly and Assembly, KENR8715 for instructions on the removal and the replacement of the phase module.STOPTest Step 4. CHECK THE STATUS OF THE DIAGNOSTIC CODE
Inspect the harness wiring connectors for the ECM and the phase module that are disconnected. Clean the contacts of the connectors. Check the wires for damage to the insulation that can be caused by excessive heat or chafing.
Reconnect all harness wiring connectors. Make sure that the connectors are fully seated and are properly fastened. Ensure that the retaining bolts are properly tightened.
Install the cabinet compartment cover for the phase module compartment. Ensure that all of