Eaton Fuller Hybrid Fault Code 3 – Motor Generator Temperature
Fault code for Eaton Hybrid Drive Systems models (MY08) EH-8E306A-U, EH-8E306A-UPG, EH-8E306A-UP, EH-8E306A-CD, EH-8E306A-T, EH-6E606B-CD, (MY09) EH-8E406A-U/P, EH-8E406A-UP, EH-8E406A-UPG, EH-8E406A-CD, EH-8E406A-CDG, EH-8E406A-CDR, EH-8E406A-T, EH-6E706B-CD, EH-6E706B-P and EH-6E706B-UPG. The Motor/Generator temperature is measured through a thermistor sensor, which is located internal to the unit. The sensor changes value based on the temperature. The Inverter supplies a 5-volt reference voltage to the sensor and measures the volt drop in the circuit.
When the Motor/Generator temperature is warm the sensor resistance is low and the Inverter detects a low-voltage (0.2 volts equals 536 °F [280 °C]). When the Motor/Generator is cold, the sensor resistance is high and the Inverter detects a high voltage (4.1 volts equals 32 °F [0 °C]).
Fault Code 3 Motor/Generator Temperature Detection
Inverter ignition voltage is greater than 7 volts and less than 16 volts (MY08)
Fault is detected when Inverter ignition voltage is greater than 7 volts and less than 16 volts (MY09)
Conditions to Set Fault Code Active
When the Motor/Generator temperature is warm the sensor resistance is low and the Inverter detects a low-voltage (0.2 volts equals 536 °F [280 °C]). When the Motor/Generator is cold the sensor resistance is high and the Inverter detects a high-voltage (4.1 volts equals 32 °F [0 °C ]). (MY08)
When the temperature sensor value is greater than 365 °F (185 °C) for 1 second. (MY09)
Fallback When Fault Code 3 is set the following conditions occur:
• Amber “Check Hybrid” light illuminates.
• Fault is stored in Hybrid Control Module (HCM) memory.
• Electric Motor/Generator Assist and Regeneration are disabled; however, the high-voltage relays remain powered.
• HCM continues to control the hybrid vehicle in a diesel-only mode.
• Transmission defaults start gear to 1st.
Conditions to Set Fault Code Inactive
Only Inactive faults can be cleared from the Transmission Electronic Control Unit (TECU) or HCM history using ServiceRanger. The TECU automatically clears the faults from history after 200 hours and the HCM automatically clears the faults from history after they have been Inactive for 200 hours.
This fault code can be caused by any of the following:
- FMI 0 (FMI 0 is set when the temperature sensor value is greater than 365 °F [185 °C] for 1 second):
- Liquid cooling system (low coolant, no coolant flow, Coolant Pump, Radiator, Radiator Fan, reservoir)
Fault Code 3 – Motor/Generator Temperature Test
Component Identification MY08 Systems:
Delphi 56-Way Mating Connector View
(Harness View – Front Side)
NOTE: Refer to the Eaton Hybrid Component and Connector Location for Connector Locations in MY08 Systems
Component Identification MY09 Systems:
Delphi 40-Way Mating Connector View
Terminal Side – Harness Connector Temperature Sensor
NOTE: Refer to the Eaton Hybrid Component and Connector Location for Connector Locations in MY09 Systems.