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 490 of 5267
6.(K616) SIGNAL CIRCUIT OPEN
Measure the resistance between the (K616) signal circuit in the Inlet Air
Pressure sensor harness connector and the (K616) signal circuit in the
ECM harness connector.
Is the resistance less than 10 Ohms?
Ye s>>
Go To 7
No>>
Repair or replace the open 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.(K668) 5-VOLT SUPPLY CIRCUIT OPEN
Measure the resistance between the (K668) 5-volt supply circuit in the
Inlet Air Pressure sensor harness connector with the (K668) 5-volt sup-
ply 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)
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8.(K616) SIGNAL CIRCUIT SHORTED TO GROUND
Measure the resistance between the (K616) signal circuit in the inlet Air
Pressure sensor connector and battery negative.
Is the resistance greater than 100 K Ohms?
Ye s>>
Go To 9
No>>
Repair the (K616) signal circuit shorted to ground or replace
the wire harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
9.(K668) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
Measure the resistance between the (K668) 5-volt supply Circuit in the
Inlet Air Pressure sensor harness connector and battery negative.
Is the resistance greater than 100 K Ohms?
Ye s>>
Go To 10
No>>
Repair the (K668) 5-volt supply circuit shorted to ground or
replace the wire harness. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MOD-
ULE - DIAGNOSIS AND TESTING)
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
10.ECM
Install the ECM harness connector.
Turn the ignition on.
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>>
Refer to the INTERMITTENT CONDITION Symptom (Diag-
nostic Procedure). (Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING)
No>>
Replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
Page 492 of 5267
P0108-INLET AIR PRESSURE SENSOR VOLTAGE TOO HIGH
For a complete wiring diagramRefer to Section 8W.
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 496 of 5267
8.ECM
Install the ECM harness connector.
Turn the ignition on.
While monitoring scan tool, use a jumper wire to connect the (K916)
Return circuit with the (K616) signal circuit at the Inlet Air Pressure sen-
sor harness connector.
Did DTC P0107 set?
Ye s>>
Refer to the INTERMITTENT CONDITION Symptom (Diag-
nostic Procedure).
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING) 0
No>>
Replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)