Eaton Fuller Hybrid Transmission Electrical Pretest

This test must be performed prior to diagnosing certain specific hybrid faults. This test verifies the quality of the standard battery system and the main power and ground supplies to the Hybrid Control Module (HCM), Transmission Electronic Control Unit (TECU), and Electronic Clutch Actuator (ECA).
Note: This test is called out in the procedures when it is required.

Electrical Pretest Detection

The power-up self-check is performed automatically each time the key is turned on. Turn the key on and watch the “Service” light. If power-up stops with the “Service” light constantly on, or it never comes on, self-check has failed.

Conditions to Set Fault Code Active

  • FMI 2 is set whenever DC/DC voltage feedback signal reads greater than 15 volts or less than 10 volts and ePTO mode is engaged.
  • FMI 4 is set if the voltage feedback is less than 15 volts and greater than 10 volts and the difference between the voltage feedback and the vehicle battery voltage is greater than 0.5 volts for 1 second or more.

Fallback:

A weak power supply can cause many issues such as shift performance, power-up or failure to crank.

Possible Causes Indicated by Eaton Fuller Hybrid Transmission Electrical Pretest

Low-voltage can be caused by the following:

  • Low batteries
  • Charging system
  • Power harness connections or fuses to TECU, HCM or ECA

Component Identification for Eaton Fuller Hybrid Transmission Electrical Pretest:

TECU - Vehicle Interface Connector

Front View
(TECU – Vehicle Interface Connector)

ECA 3-way connector fuller tranmission

ECA – 3-Way Connector

HCM - Hybrid System Interface Connector

Front View
(HCM- Vehicle Interface Connector)

Eaton Fuller ECA 8 way connector

ECA – 8-Way Connector

NOTE: Refer to the Eaton Hybrid Component and Connector Location for Connector Locations in MY08 Systems

NOTE: Refer to the Eaton Hybrid Component and Connector Location for Connector Locations in MY09 Systems.

Eaton Fuller TEC-HCM-ECA-ignition relay to battery
Warnings & Cautions

Danger: Danger indicates you will be severely injured or killed if do not follow the indicated procedure.
Warning: Warning indicates an immediate hazard, which could result in severe personal injury if you do not follow the indicated procedure.
Caution: Caution indicates vehicle or property damage could occur if you do not follow the indicated procedure.

 Note: Note indicates additional detail that will aid in the diagnosis or repair of a component/system.

Follow the specified procedures in the indicated order to avoid personal injury:

1. If the high-voltage cones are around the vehicle and the lockout is installed on the PEC, the only person that should be allowed to start the vehicle is the person who signed the lockout tag.
2. Before working on a vehicle or leaving the cab while the engine is running, you should place the shift lever in “N” set the parking brake, and block the wheels.
3. For safety reasons, always engage the service brakes prior to selecting gear positions from “N.”
4. Before starting a vehicle always be seated in the driver’s seat, select “N” on the shift control, and set the parking brakes.
5. In vehicles with ePTO, the engine and/or
Motor/Generator can start in ePTO mode. Never perform any maintenance or work on vehicle, while in this mode.
6. 12-Volt Battery positive (+) and negative (-) must be disconnected prior to any welding on any Hybrid equipped vehicle.

Caution: Follow the specified procedures in the indicated order to avoid equipment malfunction or damage.
Caution: Do not release the parking brake or attempt to select a gear until the air pressure is at the correct level.
Caution: To avoid damage to the transmission during towing place the shift lever in “N” and lift the drive wheels off the ground or disconnect the driveline.

High-Voltage Warnings & Cautions

  • Use CO2 or Dry Chemical Fire Extinguishers.
  • The high-voltage wiring is covered in orange insulation or convoluted tubing and marked with warning labels at the connectors.
  • All Eaton® Hybrid Diesel/Electric vehicles will be marked ‘Hybrid’ on the outside of the vehicle, along with the shift label on the dash.
  • Refer to OEM for specific location of chassis mounted hybrid components.
  • Do NOT cut into the orange high-voltage cables.
  • Do NOT cut into or open the PEC.
  • Do NOT cut into or open the DC/DC Converter.
  • Do NOT cut into or open the Inverter.

A buffer zone must be set up and high-voltage insulated rubber gloves (class 0 with leather protectors) are required prior to working on high-voltage. Failure to follow these instructions may result in severe personal injury or death.
The rubber-insulated gloves that must be worn while working on the high-voltage system are class 0 with leather protectors. The rubber gloves should be tested before EVERY use following the rubber insulation gloves testing procedure found in “Diagnostic Tools/Service Publications” on page 6. Failure to follow these instructions may result in severe personal injury or death.
Before inspecting or working on any high-voltage cables or components the “High-Voltage Service Shutdown and Power-Up Procedure” on page 4 should be followed. Failure to follow these instructions may result in severe personal injury or death.
The Lockout and Tagout devices should only be removed by the technician that placed the Lockout and Tagout devices on the vehicle. Failure to follow these instructions may result in severe personal injury or death.
High-voltage rubber insulated gloves (class 0 with leather protectors) must be worn when working on any
high-voltage cables. The “High-Voltage Service Shutdown and Power-Up Procedure” on page 4 must be followed prior to removing any high-voltage cables. Failure to follow these instructions may result in severe personal injury or death.
High-voltage cables and wiring are orange and contain a warning label at the connectors. High-voltage components are marked with a label. High-voltage rubber insulated gloves (class 0 with leather protectors) must be used when working on any of these components. Failure to follow these instructions may result in severe personal injury or death.

High-Voltage Service Shutdown Procedures

High-Voltage Service Shutdown and Power-Up Procedure1. Follow “High-Voltage Work Area” procedure.
2. Locate the red PEC Service Switch on the front of the PEC and push switch off.
3. Remove the Service Switch Cover and install the Lockout Bracket (J48506).
4. Fasten tag to the Lockout Bracket.
5. Ensure the PEC Service Switch can not move from the off position.
6. Allow the system to set for a minimum of 5 minutes to discharge high voltage.
7. Connect ServiceRanger and view the Data Monitor PID 116 called “High-Voltage Battery Potential.” Use SPN 520323 for J1939 connection “Battery Voltage RB” (Relay Box).
8. The voltage should be 30 volts or less. If the voltage is above 30 volts, do not work on the vehicle and contact Eaton® at 1-800-826-HELP (4357).
9. Turn ignition key off and proceed to repair or troubleshooting step.
Note: The voltage drops to zero when the key is off.

High-Voltage Service Power-Up Procedure

1. Install all high-voltage connectors into their locked positions.
2. If you are the person working on the vehicle, remove the Lockout Bracket and tag.
3. Reinstall the Lockout Bracket over the Service Switch.
4. Pull the Service Switch out and let vehicle set for 2 minutes.
5. Start vehicle when appropriate.

Eaton Hybrid Component and Connector Location

Eaton Hybrid Component and Connector Locations MY08 Systems

Eaton Hybrid Component and Connector Location MY09 Systems

Eaton Hybrid Component and Connector Locations MY09 Systems

STEP 1. Verify chassis battery voltage

  1. Key off.
  2. Inspect starter, battery and in line fuse holder connections on Electric Clutch Actuator (ECA), Hybrid Control Module (HCM), and Transmission Electronic Control Unit (TECU) for integrity.
    Note: ECA, HCM and TECU use a 30-amp fuse. Refer to OEM for locations.
  3. Measure voltage across batteries.
    • If voltage is between 11–13 volts on a 12-volt system, proceed with battery load test. Repair or replace batteries as required, go to Step 2.
    • If voltage is outside of range, repair or replace batteries and charging system as required. Repeat this step.

STEP 2. Verify ECA battery voltage and ignition status.

  1. Key on.
  2. Connect ServiceRanger to 9-Way Diagnostic Connector in the cab.
  3. Select the “Data Monitor” option and view the following parameters under the hybrid (clutch actuator) list:
    • PID 132 “Clutch Actuator Battery Voltage.”
    • PID 160 “Clutch Actuator Ignition Switch Status.”
      Note: If the clutch parameters can not be viewed on ServiceRanger you must check the power supply to the ECA with a voltmeter.
    • If PID 132 is within 0.6 volts of battery voltage and PID 160 reads “1”, go to Step 3.
    • If either voltage is out of range, repair main power or ignition supply to the ECA. Repeat this step.

STEP 3. Verify HCM battery voltage and ignition status.

  1. Select the “Data Monitor” option and view the following parameters under the Hybrid Control Module list:
    • PID 165 Battery Potential Voltage
    • PID 166 Ignition Switch Status
      Note: If the Battery Potential Voltage or Ignition Switch Status can not be viewed on ServiceRanger, you must check the power supply to the HCM with a voltmeter.
    • If PID 165 is within 0.6 volts of battery voltage and PID 166 reads “1”, go to Step 4.
    • If either voltage is out of range, repair the main power or ignition supply to the HCM. Repeat this step.

STEP 4. Verify TECU battery and switched voltage.

  1. Select the “Data Monitor” option and view the following parameters under the hybrid Transmission list:
    • PID 168 Battery Potential Voltage.
    • PID 158 Battery Potential Voltage Switched.
      Note: If the “Battery Potential Voltage” or “Battery Potential Voltage Switched” can not be viewed on ServiceRanger, check the power
      supply to the TECU with a voltmeter.
    • If PID 168 is within 0.6 volts of battery voltage and PID 158 is within 0.6 volts of ignition voltage, test is complete. Return to the fault or symptom procedure that directed you to this step.
    • If either voltage is out of range, repair main power or ignition supply to the TECU. Repeat this step.

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