Cummins ISB4.5 CM2150 Fault Code: 221 PID: 108 SPN: 108 FMI: 3 Barometric Pressure Sensor Circuit – Voltage Above Normal or Shorted to High Source.
Circuit Description
The ambient air pressure sensor responds to pressure changes in the atmospheric pressure. The pressure changes occur based on elevation that the engine is presently operating at. The ambient air pressure sensor has a 5 volt supply circuit, a sensor signal voltage, and a return circuit.
The ambient air pressure sensor provides a signal to the ECM on the ambient air pressure sensor signal circuit. This sensor signal voltage changes based on the pressure of the atmosphere. The ECM will detect a low signal voltage when the vehicle is operating at high altitudes. The ECM will detect a high signal voltage when the vehicle is operating at sea level altitudes.
Component Location
The barometric pressure sensor is mounted on the main branch of the engine harness near 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 ambient air pressure signal voltage is greater than 4.75-VDC for more than 10 seconds.
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.
-Engine torque could possibly be reduced.
-A default value of the ambient pressure reading is used.
Conditions for Clearing the Fault Code
-To validate the repair, start the engine and let it idle for 1 minute.
For engines equipped with SCR aftertreatment:
-This fault code can not be cleared with INSITE™ electronic service tool.
-The ECM will turn off the amber CHECK ENGINE lamp and/or MIL immediately after the diagnostic runs and passes.
-Use INSITE™ electronic service tool to verify the fault code is inactive.
-The inactive fault code will be cleared from the memory after 9600 hours of engine operation without a reoccurrence.
For all other engines:
-The ECM will turn off the amber CHECK ENGINE lamp after the diagnostic runs and passes.
-For On-Board Diagnostics (OBD) engines, the ECM will turn off the 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 fault codes, as well as extinguish the MIL for OBD applications.
Shop Talk
The barometric pressure sensor shares supply and return wires in the engine harness with other sensors. Opens and shorts in the engine harness can cause multiple fault codes to be active. Before troubleshooting Fault Code 221, check for multiple fault codes.
Possible Causes
-Open return circuit in the harness, connectors, or sensor
-Signal circuit shorted to sensor supply or battery voltage.
-
10 IN 1 FOR CAT SIS Caterpillar 2021 Full Service Dealer INCLUDING CAT 2019 C
CAT $110.00Rated 0 out of 5 -
Eaton Service Ranger 4.9 Engineering 4.9 [05.2021] Engineering Level ( 1 PC )
Eaton $67.00Rated 0 out of 5 -
Volvo Intermediate Storage File Encryptor/Decryptor (Editor) VISFED 0.3.2
Trucks software $35.00Rated 0 out of 5
Related products
-
Allison 1000 & 2000 Gen 4 Fault Codes: P0846 Transmission Pressure Switch Solenoid D Circuit Stuck Open
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P2773 Torque Control Request Ignored – ECM/TCM
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P2810 Solenoid G Electrical
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 P0719 Brake Switch ABS Input Low
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: U0032 J1850 (Class 2) Serial Data Communication Link High
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P0123 Pedal Position Sensor Circuit High Voltage
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P0872 Transmission Pressure Switch Solenoid E Circuit Stuck Closed
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P0876 Transmission Reverse Pressure Switch Circuit Stuck Open
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P1892 Throttle Position Sensor Pulse Width Modulation (PWM) Signal High Input
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P0122 Pedal Position Sensor Circuit Low Voltage
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: U0073 CAN Bus Reset Counter Overrun
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: U2104 CAN Bus Reset Counter Overrun
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: U2105 CAN Bus ECM Error
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P0870 Transmission Pressure Switch Solenoid E Circuit
1000 & 2000 Gen 4 $50.00Rated 0 out of 5 -
Allison 1000 & 2000 Gen 4 Fault Codes: P0847 Transmission Pressure Switch Solenoid D Circuit Stuck Closed
1000 & 2000 Gen 4 $50.00Rated 0 out of 5
-
SERVICE MANUAL 3000 AND 4000 SERIES GEN 4 GENERATION – ALLISON
Allison$19.00Original price was: $19.00.$17.00Current price is: $17.00.Rated 0 out of 5 -
SERVICE MANUAL Eaton Fuller® HD FR/FRO TransmissionsTRSM2400April 2013
TRUCK MANUALSRated 0 out of 5 -
SERVICE MANUAL Carrie Genesis R70 Genesis R90 Genesis TR1000 Multi -Temp
CARRIE $25.00Rated 0 out of 5