Cummins ISB CM850 (2003-06) Fault Code: 1848 PID: 105 SPN: 105 FMI: 10 Intake Manifold 1 Temperature ? Abnormal Rate of Change. The intake manifold temperature sensor is not responding to a change in engine operating conditions.

Posted by PerDiezel Solutions on January 18, 2026

The engine intake manifold temperature is monitored during engine warm-up. If the engine intake manifold temperature reading is not changing to match the engine operating conditions, the intake manifold temperature sensor is then determined to be stuck in-range and this fault code is logged. The ECM must not see engine speed for a period of eight hours before this diagnostic will run.

Possible causes:

1)Stuck in-range engine intake manifold temperature sensor reading.
2)High resistance in the engine intake manifold temperature sensor signal or return lines.

On-Board Diagnostics (OBD) Information (Euro 4 and Euro 4 Stage 1+ Certified Engines):

1)The ECM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2)The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. The MIL lamp and fault code can also be cleared using the INSITE? service tool.
3)The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

Possible repairs:

1)Replace the engine intake manifold temperature sensor.
2)Replace the ECM.
3)Repair or replace the engine harness.

Cummins ISB CM850 (2003-06) Fault Code: 1846 PID: SPN: 97 FMI: 4 Water-in-Fuel Indicator Sensor Circuit – Voltage Below Normal or Shorted to Low Source (For Generator Engines Only). Low voltage detected at the water-in-fuel indicator circuit.

Cummins ISB CM850 (2003-06) Fault Code: 1845 PID: SPN: 97 FMI: 3 Water-in-Fuel Indicator Sensor Circuit – Voltage Above Normal or Shorted to High Source (For Generator Engines Only). High voltage detected at the water-in-fuel indicator circuit.

Cummins ISB CM850 (2003-06) Fault Code: 1718 PID: SPN: 1322 FMI: 11 Engine Misfire for Multiple Cylinders ? Condition Exists. Engine misfire has been detected in multiple cylinder numbers.

Cummins ISB CM850 (2003-06) Fault Code: 1717 PID: SPN: 3241 FMI: 15 Exhaust Gas Temperature 1 ? Data Valid but Above Normal Operational Range ? Least Severe Level. High catalyst inlet temperature has been detected.

Cummins ISB CM850 (2003-06) Fault Code: 1716 PID: SPN: 411 FMI: 11 Auxiliary Temperature Sensor Input 1 Circuit – Root Cause Not Known. High temperature detected by the OEM temperature sensor or by the engine coolant temperature sensor.

Cummins ISB CM850 (2003-06) Fault Code: 1713 PID: SPN: 3363 FMI: 0 Catalyst Tank Heater Circuit – Data Valid But Above Normal Operating Range – Moderately Severe Level. The catalyst tank heater is continuously in the on position

WARNING!