CAT 3126B Fault Code: 231-02 PID: Flash Code 58 SPN: 639 FMI: 2 J1939 Data Incorrect

Posted by PerDiezel Solutions on January 12, 2026

This condition indicates that the J1939 data link is receiving information from a specified device but the information is incomplete or corrupted. The parameter “Powertrain Data Link” must be programmed to J1939.

One of the following conditions must be met:

•The device is broadcasting a fault code.
•The Engine Control Module (ECM) is unsuccessful in receiving a specific message from a device.
•The device is broadcasting a code that is not supported.

The power train data link is designed to offer electronically controlled Anti-Lock Brakes (ABS), traction control systems, and/or transmission controls. This is accomplished by a momentary reduction of engine rpm and/or engine torque, that is triggered by a signal from an off-engine control module for the ABS, the traction control, or the transmission. An off-engine control module is a control module that is not part of theCaterpillar engine control system.

Possible Causes:

1) ECM Connection/Harness
2) Other devices on the J1939 (ABS, Body Controller, Transmission, etc…) are failing causing the issue
3) Improper programming in ECM
4) ECM Failure

CAT 3126B Fault Code: 253-14 PID: Flash Code 56 SPN: FMI: Truck Manufacturer Paremater Not Programmed

CAT 3126B Fault Code: 253-02 PID: Flash Code 56 SPN: 630 FMI: 2 Check Customer or System Parameters

CAT 3126B Fault Code: 168-02 PID: Flash Code 51 SPN: 168 FMI: 2 ECM Battery Power Intermittent

CAT 3126B Fault Code: 168-01 PID: Flash Code 51 SPN: 168 FMI: 1 Low ECM Battery Power

CAT 3126B Fault Code: 168-00 PID: Flash Code 51 SPN: 168 FMI: 0 Excessive ECM Battery Power

CAT 3126B Fault Code: 70-06 PID: Flash Code 49 SPN: 729 FMI: 6 Inlet Air Heater Short Circuit

WARNING!