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. Read below to learn how to test, clear and fix fault code errors for your Freightliner, Mack, Peterbilt, Kenworth, Volvo, International, and heavy-duty truck and equipment. The High-Voltage Relays are located inside the Power Electronics Carrier (PEC) in the Relay Box unit. There is 1 precharge relay on the positive side, an additional relay on the positive, and 1 on the negative for a total of 3. These relays are normally open when the system is off. The relays are controlled through the Inverter.
Fault Code 116 – High Voltage Relays Detection
The following preconditions must be met before the system detects the fault:
- Inverter ignition voltage is greater than 7 volts and less than 16 volts.
Note: When troubleshooting an Inactive code refer to the Product Diagnostic Mode (PDM)
Conditions to Set Fault Code Active
- FMI 10 is set when the Inverter detects the input voltage measured at the capacitor is less than 210 volts within 3 seconds after the sub-relay closed in the Relay Box.
- FMI 14 is set when only the negative relay in the Relay Box is on and capacitor voltage decreases less than 10 volts/5 seconds when initial capacitor voltage was greater than 200 volts and motor speed less than 500 min-1, or there is a detect error in the initial check.
Fallback When Fault Code 116 is set the following conditions occur:
- Amber “Check Hybrid” light blinks for FMI 10 and remains solid for FMI 14.
- Fault is stored in HCM memory.
- Inverter shuts high-voltage system off.
- 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 the fault has been Inactive for 200 hours.
This fault code can be caused by any of the following:
- FMI 10
- DC high-voltage cable
- DC cable interlock loops
- Inertia Switch
- Service Switch
- FMI 14