Eaton Fuller Hybrid Transmission Fault Code 36 – J1939 Engine Message (TECU)
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. J1939 is a high-speed twisted pair 250K data link with one 120 ohm resistor at each end of the link. The Transmission Electronic Control Unit (TECU) is connected to the J1939 data link at the 38-Way Connector. This link is used to transmit information to the Hybrid Control Module (HCM) and communicate with other modules on the network such as the Engine Control Unit (ECU).
Fault Code 36 – J1939 Engine Message (TECU) Detection
The following preconditions must be met before the system detects the fault:
- TECU ignition voltage is greater than 7 volts and less than 16 volts.
- TECU Battery Voltage Low fault is Inactive.
- TECU J1939 data link fault is Inactive.
Conditions to Set Fault Code Active
- FMI 14 is set when the TECU fails to receive engine ECU data like engine torque for 5 seconds or greater, and it is still communicating with other modules on J1939.
Note: When troubleshooting an Inactive code refer to the Product Diagnostic Mode (PDM)
Fallback When Fault Code 36 is set the following conditions occur:
- Red “Service” light illuminates and an “F” flashes in the gear display.
- Fault is stored in TECU memory.
- If the fault occurs while moving, the TECU goes into AutoShift Fallback mode.
- Once the vehicle stops, start and reverse gears can be selected and the transmission operates in AutoSelect mode.
- If the fault occurs at power up, the vehicle will crank.
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 14
- J1939 data link