ECU Calibration Memory Fault - Received Network Data in Error
What does JD-SPN631-FMI19 mean?
The JD-SPN631-FMI19 (John Deere PowerTech) diesel fault code means: ECU Calibration Memory Fault - Received Network Data in Error. This is a serious severity code.
Common Symptoms
- ECU faults stored with no drivable symptom, or failure to wake ECU
- Service package mismatch (Gold / Silver / Bronze)
- SERVICE SOON or CHECK ENGINE on DisplayPort
Probable Causes (Ranked by Likelihood)
- Incorrect software calibration installed after service package swap Likely
- Corrupt EEPROM after power cycle during programming Possible
- CAN bus fault preventing ECU identity handshake Possible
- Internal ECU failure requiring replacement Less Likely
Step-by-Step Diagnostic Procedure
Connect Service ADVISOR and read ECU ID + calibration revision; compare to current PIP.
Verify CAN backbone terminating resistors measure ~60 ohms across CAN H/L with key off.
Re-flash with the latest OEM calibration file for the serial-number range.
If reflash fails, escalate to dealer for ECU exchange -- security keys required.
Frequently Asked Questions
What is John Deere fault code SPN 631 FMI 19?
On John Deere PowerTech engines, SPN 631 FMI 19 means: ECU Calibration Memory Fault - Received Network Data in Error. Serious code -- address promptly to avoid inducement / further damage. Service package mismatch (Gold/Silver/Bronze) will generate SPN 631 after ECU reflash -- confirm correct calibration file per serial number.
Can I keep using my John Deere tractor with SPN 631 FMI 19?
Serious fault -- you can move the machine to a shop but don't run it under load. Diagnose with John Deere Service ADVISOR via an EDL v3 / CF3 interface.
How much does it cost to fix John Deere SPN 631 FMI 19?
Repair cost range: $600-$2,400 ECU reflash or replacement. Dealer labor on large tractors runs $180-$240/hr in 2026.