25 March, 2025CAT 3126B Fault Code: 84-02 PID: Flash Code 36 SPN: FMI: Invalid Vehicle Speed Signal The Ecm detects one of the following after attempting to actuacte the injector solenoid: – An open circuit in the injector wiring. – An internal open circuit in the injector solenoid. Share on Facebook Opens in a new window. Tweet on Twitter Opens in a new window. Pin on Pinterest Opens in a new window. Back to blog Leave a comment Name * Email * Comment * Please note, comments need to be approved before they are published.