Eaton Fuller Hybrid Fault Code 22 – J1939 ABS Message Fault (HCM)
Fault code for Eaton Hybrid Drive Systems models (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 HCM is connected to the J1939 Data Link at the 38-Way Connector. This link is used to transmit information to the HCM as well as communicate or receive data from the other modules on the network like the ABS module.
Fault Code 22 – J1939 ABS Message Fault (HCM) Detection
The following preconditions must be met before the system detects the fault:
- HCM ignition voltage is greater than 7 volts and less than 16 volts.
- J1939 Data Link communication fault is not Active.
Conditions to Set Fault Code Active
- FMI 9 is set when the HCM fails to receive ABS messages and there are no Active J1939 faults. In PDM mode (FMI 2) this fault is set if 3 consecutive messages (EBC1) are not received.
- FMI 14 is set when the HCM receives an Active ABS signal (SPN563) out of range or the ABS “Fully Operational Signal” (SPN1243) is not present for 1 second.
Fallback When Fault Code 22 is set the following conditions occur:
- Amber “Check Hybrid” light displays.
- Fault is stored in HCM memory.
- If the fault occurs while moving, the operation mode goes into AutoShift only.
- Electric motor/generator Assist and Regeneration are disabled; however, the high-voltage relays remain powered.
- Transmission defaults start gear to 1st.
This fault code can be caused by any of the following:
- FMI 2, 9
- J1939 Data Link
- ABS Module
- FMI 14
- ABS Module configured to communicate on J1708 or analog instead of J1939.
- ABS Module reporting an Active fault.
Fault Code 22 – J1939 ABS Message Fault (HCM) Test
Front Harness View
(HCM – Vehicle Interface Connector)