Cummins ISB4.5 CM2150 Fault Code: 346 PID: 253 SPN: 630 FMI: 12 Engine Control Module Calibration Memory Software – Bad Intelligent Device or Component.

Posted by PerDiezel Solutions on January 21, 2026

Circuit Description
The accelerator interlock switch and powertrain protection torque limit switch, clutch pedal position switch and engine protection shutdown manual override switch, idle shutdown accessory relay and engine brake lamp output, switched maximum engine operating speed and governor type switch are all outputs or switched inputs from the ECM that can be enabled or disabled using INSITE™ electronic service tool. Many of the outputs and switched inputs share a common wire on the OEM wiring harness. The following features share common wires in the OEM harness:

-Accelerator Interlock Switch and Powertrain Protection Torque Limit Switch
-Clutch Pedal Position Switch and Engine Protection Shutdown Manual Override Switch
-Idle Shutdown Accessory Relay and Engine Brake Lamp Output
-Switched Maximum Engine Operating Speed and Governor Type Switch

Component Location
The output or switched inputs to this diagnostic are found in the OEM harness.

Conditions for Running the Diagnostics
This diagnostic runs at initial key ON only.

Conditions for Setting the Fault Codes
The ECM detects that features that share a common OEM harness input or output to the ECM are simultaneously enabled at the same time.

Action Taken When the Fault Code is Active
The ECM will set the fault code active immediately after the diagnostic is set. The features that are in conflict may not operate correctly.

Conditions for Clearing the Fault Code
The fault code will be set inactive at key on when the conflicting features have been adjusted correctly.

Shop Talk
Many of the outputs and switched inputs share a common wire on the OEM wiring harness. If two features that share a common OEM wire are enabled simultaneously in the ECM, this fault code will be logged. To disable the fault code, disable one of the features on the shared OEM wire. For example, if the accelerator interlock switch and powertrain protection torque limit switch are both enabled in the ECM, either disable one of the features with INSITE™ electronic service tool or configure one of the features to be multiplexed using the SAE J1939 multiplexing feature.

Cummins ISB4.5 CM2150 Fault Code: 343 PID: SID 254 SPN: 629 FMI: 12 Electronic Control Module Warning Internal Hardware Failure – Bad Intelligent Device or Component.

Cummins ISB4.5 CM2150 Fault Code: 339 PID: SID 87 SPN: 1267 FMI: 4 Idle Shutdown Vehicle Accessories Relay Driver Circuit – Voltage Below Normal, or Shorted to Low Source.

Cummins ISB4.5 CM2150 Fault Code: 338 PID: SID 87 SPN: 1267 FMI: 3 Idle Shutdown Vehicle Accessories Relay Driver Circuit – Voltage Above Normal, or Shorted to High Source.

Cummins ISB4.5 CM2150 Fault Code: 334 PID: 116 SPN: 110 FMI: 2 Engine Coolant Temperature – Data Erratic Intermittent or Incorrect.

Cummins ISB4.5 CM2150 Fault Code: 332 PID: SID 6 SPN: SID 6 FMI: 5 Injector Solenoid Driver Cylinder 4 Circuit – Current Below Normal or Open Circuit.

Cummins ISB4.5 CM2150 Fault Code: 331 PID: SID 6 SPN: 652 FMI: 5 Injector Solenoid Driver Cylinder 2 Circuit – Current Below Normal or Open Circuit.

WARNING!