Page 488 of 5267

When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.
Set Condition:
The circuit voltage to the ECM falls below a calibrated threshold for a certain period of time.
Possible Causes
OTHER DTC’S PRESENT
INLET AIR PRESSURE SENSOR
INLET AIR SENSOR (K616) SIGNAL CIRCUIT SHORTED TO THE (K690) RETURN CIRCUIT
INLET AIR PRESSURE SENSOR (K668) SUPPLY CIRCUIT SHORTED TO THE RETURN CIRCUIT
(K616) SIGNAL CIRCUIT OPEN
(K668) 5-VOLT SUPPLY CIRCUIT OPEN
(K616) SIGNAL CIRCUIT SHORTED TO GROUND
(K668) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
ECM
INTERMITTENT CONDITION
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.OTHER DTC’S PRESENT
Ignition on, engine not running.
With the scan tool, read DTCs.
Do you have multiple DTC’s?
Ye s>>
Repair other DTC’s first.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 2
2.SENSOR VOLTAGE
Disconnect the Inlet Air Pressure sensor harness connector.
Check connectors - Clean/repair as necessary.
Measure the voltage between the (K668) 5-volt supply circuit and
(K690) return circuit of the sensor harness connector.
Is the voltage between 4.5 and 5.5 volts?
Ye s>>
Go To 3
No>>
Go To 5
Page 489 of 5267

3.INLET AIR PRESSURE SENSOR
While monitoring scan tool, use a jumper wire to connect the (K668)
5-volt supply circuit with the (K616) signal circuit at the sensor harness
connector.
Does the scan tool show a pressure sensor out of range high
DTC?
Ye s>>
Replace the Inlet Air Temperature/Pressure sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
No>>
Go To 4
4.INLET AIR PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO THE RETURN CIRCUIT
Turn the ignition off.
Disconnect the ECM harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance between the (K616) signal circuit and (K690)
return circuit in the Inlet Air pressure sensor harness connector.
Is the resistance greater than 100K Ohms?
Ye s>>
Go To 5
No>>
Repair or replace wiring harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
5.SENSOR (K668) 5-VOLT SUPPLY CIRCUIT SHORTED TO THE (K690) RETURN CIRCUIT
Measure the resistance between the (K668) 5-volt supply circuit and
(K690) return circuit in the Inlet Air Pressure sensor harness connector.
Is the resistance greater than 100K Ohms?
Ye s>>
Go To 6
No>>
Repair the short or replace the harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
Page 493 of 5267

When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.
Set Condition:
The circuit voltage to the ECM is above a calibrated threshold for a certainperiod of time.
Possible Causes
OTHER DTC’S PRESENT
INLET AIR PRESSURE SENSOR
INLET AIR PRESSURE SENSOR (K616) SIGNAL CIRCUIT SHORTED TO VOLTAGE
INLET AIR SENSOR (K668) 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
(K616) SIGNAL CIRCUIT SHORTED TO (K668) 5-VOLT SUPPLY
(K690) RETURN CIRCUIT OPEN
ECM
INTERMITTENT CONDITION
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.OTHER DTC’S PRESENT
Ignition on, engine not running.
With the scan tool, read DTCs.
Do you have multiple DTC’s?
Ye s>>
Repair other DTC’s first.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 2
2.CHECKING (K668) 5-VOLT SUPPLY CIRCUIT AND THE (K690) RETURN CIRCUIT
Disconnect the Inlet Air Pressure sensor harness connector.
Measure the voltage between the (K668) 5-volt supply circuit and
(K690) return circuit of the Inlet Air Pressure sensor harness connector.
Is the voltage between 4.5 and 5.5 volts?
Ye s>>
Go To 3
No>>
Go To 4
Page 494 of 5267

3.INLET AIR PRESSURE SENSOR
While monitoring scan tool, use a jumper wire to connect the (K690)
Return circuit to the (K616) signal circuit at the Inlet Air Pressure sensor
harness connector.
Does the scan tool show a P0107 Inlet Air Pressure Sensor
Low DTC.
Ye s>>
Replace the Inlet Air Temperature/Pressure sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
No>>
Go To 4
4.INLET AIR SENSOR (K616) SIGNAL CIRCUIT SHORTED TO VOLTAGE
Disconnect the ECM harness connectors.
NOTE: Check connectors - Clean/repair as necessary.
Measure the voltage between the (K616) signal circuit of the Inlet Air
Pressure sensor connector and battery negative.
Is the voltage less than 1 volt?
Ye s>>
Go To 5
No>>
Repair or replace short to voltage.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
5.(K668) 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
Measure the voltage between the (K668) 5-volt supply circuit of the sen-
sor connector and battery negative.
Is the voltage less than 1 volt?
Ye s>>
Go To 6
No>>
Repair the short to voltage or replace the harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
Page 495 of 5267

6.SIGNAL CIRCUIT SORTED TO (K668) 5-VOLT SUPPLY
Turn the ignition off.
Measure the resistance between the (K616) signal circuit and the
(K668) 5-volt supply circuit of the Inlet Air Pressure sensor harness con-
nector.
Is the resistance less than 10 Ohms?
Ye s>>
Go To 7
No>>
Repair or replace the shorted wiring harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
7.(K690) RETURN CIRCUIT OPEN
Disconnect the ECM harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance between the (K690) return circuit in the Inlet Air
Pressure sensor harness connector with the (K690) return circuit in the
ECM harness connector.
Is the resistance less than 10 Ohms?
Ye s>>
Go To 8
No>>
Repair or replace the Engine harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
Page 500 of 5267

When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.
Set Condition:
The circuit voltage to the ECM falls below a calibrated threshold for a certain period of time.
Possible Causes
INTAKE AIR TEMP SENSOR OUT OF SPEC
INTERMITTENT CONDITION
(K21) SENSOR SIGNAL CIRCUIT SHORTED TO GROUND CIRCUIT
WIRING HARNESS SHORTED
(F855) 5-VOLT SUPPLY CIRCUIT OPEN
ECM
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
1.INTAKE AIR TEMP SENSOR OUT OF SPEC
Disconnect the Intake Air Temperature sensor harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance of the Intake Air Temp sensor.
Is the resistance between 300 and 90k ohms?
Ye s>>
Go To 2
No>>
Replace the Intake Air temperature sensor/MAP sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
2.INTERMITTENT CONDITION
Reconnect the circuit.
Turn the ignition on.
With the scan tool, erase DTCs.
With the scan tool, read DTCs.
Did the DTC reappear?
Ye s>>
Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 3
Page 501 of 5267
3.(K21) SIGNAL CIRCUIT SHORTED TO GROUND CIRCUIT
Turn the ignition off.
Disconnect the ECM harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance between the engine ground and the tempera-
ture sensor (K21) signal circuit at the sensor harness connector.
Istheresistancemorethan100kohms?
Ye s>>
Go To 4
No>>
Repair or replace the engine wiring harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
4.WIRING HARNESS SHORTED
Measure the resistance between the (K21) signal circuit and all other
circuits at the ECM harness connector.
Istheresistancemorethan100kohms?
Ye s>>
Go To 5
No>>
Repair or replace the shorted wiring harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
Page 505 of 5267

When Monitored:
With ignition on and battery voltage greater than 10.4 volts.
Set Condition:
The circuit voltage to the ECM is above a calibrated threshold for a certainperiod of time.
Possible Causes
FAILED SENSOR
INTERMITTENT CONDITION
(K21) SENSOR SIGNAL CIRCUIT OPEN
(K916) RETURN CIRCUIT OPEN
SHORT IN HARNESS
ECM
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.FAILED SENSOR
Turn the ignition off.
Disconnect the IAT sensor harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance of the IAT sensor.
Is the resistance between 300 and 90k ohms?
Ye s>>
Go To 2
No>>
Replace the Intake Air Temperature Sensor/map sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
2.INTERMITTENT CONDITION
Reconnect the IAT harness connector.
Turn the ignition on.
With the scan tool, erase DTCs.
With the scan tool, read DTCs.
Is P0113 still set?
Ye s>>
Go To 3
No>>
Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)