Cummins ISB4.5 CM2150 Fault Code: 697 PID: 21 SPN: 1136 FMI: 3 ECM Internal Temperature Sensor Circuit – Voltage Above Normal or Shorted to High Source.

Posted by PerDiezel Solutions on January 20, 2026

Circuit Description
The engine control module (ECM) has an internal temperature sensor that is used to measure the temperature inside the ECM.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault Codes
The ECM detects that the internal temperature sensor circuit is shorted high.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE light immediately after the diagnostic runs and fails.

Conditions for Clearing the Fault Code
-To validate the repair, start the engine and let it idle for 1 minute.
-The ECM will turn off the amber CHECK ENGINE light immediately after the diagnostic runs and passes.
-This fault code can also be cleared with INSITE™ electronic service tool.

Shop Talk
This sensor is located internally to the ECM. No troubleshooting is possible for this fault code. If the fault code is active, the ECM must be replaced.

Cummins ISB4.5 CM2150 Fault Code: 693 PID: 351 SPN: 1172 FMI: 2 Turbocharger 1 Compressor Intake Temperature – Data Erratic, Intermittent, or Incorrect.

Cummins ISB4.5 CM2150 Fault Code: 692 PID: 351 SPN: 1172 FMI: 4 Turbocharger 1 Compressor Intake Temperature Circuit – Voltage below normal, or shorted to low source.

Cummins ISB4.5 CM2150 Fault Code: 691 PID: 351 SPN: 1172 FMI: 3 Turbocharger 1 Compressor Intake Temperature Sensor Circuit – Voltage Above Normal or Shorted to High Source.

Cummins ISB4.5 CM2150 Fault Code: 689 PID: 190 SPN: 190 FMI: 2 Engine Crankshaft Speed/Position – Data Erratic, Intermittent, or Incorrect.

Cummins ISB4.5 CM2150 Fault Code: 688 PID: SPN: 98 FMI: 0 Engine Oil Level – Data Valid but Above Normal Operating Range – Most Severe Level.

Cummins ISB4.5 CM2150 Fault Code: 687 PID: 103 SPN: 103 FMI: 1 Turbocharger 1 Speed – Data Valid but Below Normal Operating Range – Moderately Severe Level.

WARNING!