Cummins ISX11.9 CM2250 (2010-12) Fault Code: 2973 PID: 102 SPN: 102 FMI: 2 Intake Manifold 1 Pressure- Data Erratic, Intermittent, or Incorrect

Circuit Description
The engine control module (ECM) provides a 5 volt supply to the intake manifold pressure sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The intake manifold pressure sensor provides a signal to the ECM on the intake manifold pressure sensor signal circuit. This sensor signal voltage changes based on the pressure in the intake manifold.

Component Location
The intake manifold 1 pressure/temperature sensor is located in the air intake manifold.

Conditions for Running the Diagnostics
This diagnostic consists of two parts:

One part runs immediately after the keyswitch is turned OFF, and the engine coolant temperature is above 70?C or 158?F.

The second part occurs when the engine is operating.

Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the intake manifold pressure sensor was reading higher or lower than expected at keyoff or during normal engine operation.

Action Taken When the Fault Code is Active
The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
A default value of the intake manifold pressure reading is used.
Diesel exhaust fluid injection into the aftertreatment system is disabled.
Active and stationary regeneration of the diesel particulate filter will be disabled.
Exhaust Gas Recirculation (EGR) valve operation will be disabled.
Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.
Conditions for Clearing the Fault Code
To validate the repair, first ensure the engine coolant temperature is above 70?C or 158?F. Operate the engine if necessary.
Cycle the keyswitch to the ON position for 30 seconds, then cycle the keyswitch to the OFF position for 30 seconds. Start the engine and let it idle for 1 minute.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
The Reset All Faults command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk
This diagnostic consists of two parts. At key OFF, the sensor readings for intake manifold pressure, barometric air pressure, oil pressure (if available), and exhaust gas pressure are compared to each other. This fault code occurs if the intake manifold pressure sensor reading is different from the other sensor readings. This check is only done once after the keyswitch is turned OFF. This fault can also be set active when the intake manifold pressure is too high or low for the current engine operating conditions when the engine is running. The ECM compares the intake manifold pressure reading to turbocharger speed to determine if the pressure reading is valid.

Possible causes of this fault are:

A damaged turbocharger speed sensor
A damaged barometric pressure sensor
Leaks in the air intake system between the turbocharger and intake manifold
Restriction in the charge-air cooler
A damaged intake manifold pressure sensor
A damaged turbocharger compressor intake temperature sensor.

Possible Cause:
1) Barometric Pressure Sensor failure
2) Exhaust manifold pressure sensor failure
3) Engine intake manifold pressure/temperature sensor failure
4) ECM failure
5) Charge-air cooler failure
6) Turbocharger speed sensor failure