sensor DODGE RAM SRT-10 2006 Service Repair Manual

P0072-INLET AIR TEMP SENSOR VOLTAGE TOO LOW
For a complete wiring diagramRefer to Section 8W.

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
SENSOR OUT OF SPEC
HARNESS SHORTED (SENSOR SIDE)
(K668) 5-VOLT SUPPLY OPEN
HARNESS SHORTED (ECM SIDE)
INTERMITTENT CONDITION
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.INLET AIR TEMP SENSOR OUT OF SPEC
Turn the ignition off.
Disconnect the Inlet Air Temp sensor harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance of the temperature sensor.
Is the resistance between 300 and 90k ohms?
Ye s>>
Go To 2
No>>
Replace the sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 9 - ENGINE- DIAGNOSIS
AND TESTING)
2.INTERMITTENT CONDITION
Reconnect the Inlet Air Temp Sensor harness connector.
Turn the ignition on.
With the scan tool, erase DTCs.
With the scan tool, read DTCs.
Did the DTC return?
Ye s>>
Go To 3
No>>
Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)

3.HARNESS SHORTED (INLET AIR TEMPERATURE SENSOR SIDE)
Turn the ignition off.
Disconnect the inlet Air Temp sensor harness connector.
Disconnect the ECM harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance between the engine ground and the (K615)
temperature sensor signal circuit at the sensor connector.
Istheresistancemorethan100kohms?
Ye s>>
Go To 4
No>>
Repair or replace the Engine harness shorted.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING)
4.HARNESS SHORTED (ECM SIDE)
Measure the resistance between the (K615) signal circuit and all other
circuits at the ECM harness connector.
Istheresistancemorethan100kohms?
Ye s>>
Go To 5
No>>
Repair or replace the ECM harness shorted.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING)

5.(K668) 5-VOLT SUPPLY CIRCUIT
Reconnect the ECM harness connector.
Turn the ignition on.
Measure the voltage between the (K668) supply circuit and the (K690)
return circuit in the Air Temp sensor harness connector.
Is the voltage between 4.5 and 5.5 volts?
Ye s>>
Go To 6
No>>
Go To 7
6.ECM
Reconnect the Air Temp sensor harness connector.
Reconnect the ECM harness connector.
With the scan tool, erase DTCs.
While monitoring with scan tool, disconnect the Air Temp sensor harness connector.
Did the DTC P0073 set?
Ye s>>
Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure) (Referto9-ENGINE-
DIAGNOSIS AND TESTING).
No>>
Replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 9 - ENGINE- DIAGNOSIS
AND TESTING)
7.(K668) 5-VOLT SUPPLY OPEN
Disconnect the ECM harness connectors.
Measure the voltage at the (K668) 5-volt supply circuit at the ECM har-
ness connector.
Is the voltage between 4.5 and 5.5 volts?
Ye s>>
Fix or repair the (K668) 5-volt supply circuit shorted to volt-
age.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING)
No>>
Replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING)

P0073-INLET AIR TEMP SENSOR VOLTAGE TOO HIGH
For a complete wiring diagramRefer to Section 8W.

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
DTC RETURNS
INLET AIR TEMPERATURE SENSOR
(K615) SIGNAL CIRCUIT OPEN
(K690) RETURN CIRCUIT OPEN
(K615) SIGNAL CIRCUIT SHORTED
INTERMITTENT CONDITION
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.DTC RETURNS
Turn the ignition on.
With the scan tool, erase DTCs.
With the scan tool, read DTCs.
With the scan tool, record all Freeze frame data.
Did the DTC return?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
2.INLET AIR TEMPERATURE SENSOR
Turn the ignition off.
Disconnect the Inlet Air Temp sensor harness connector.
Check connectors - Clean/repair as necessary.
Measure the resistance of the Inlet Air temp sensor
Is the resistance between 300 and 90k ohms?
Ye s>>
Go To 3
No>>
Replace the Inlet air temperature sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING).

3.RESISTANCE CHECK
Disconnect the ECM harness connector.
Check connectors - Clean/repair as necessary.
Reconnect the Inlet Air Temp sensor harness connector.
Measure the resistance between the (K615) inlet air temperature sensor
signal circuit and (K690) return circuit at the ECM connector.
Is the resistance between 300 and 90k ohms?
Ye s>>
Go To 6
No>>
Go To 4
4.(K615) INLET AIR TEMPERATURE SIGNAL CIRCUIT OPEN
Disconnect the inlet Air Temp sensor harness connector.
Measure the resistance of the (K615) inlet air temperature sensor signal
circuit between the sensor harness connector and the ECM harness
connector.
Is the resistance less than 10 Ohms?
Ye s>>
Go To 5
No>>
Repair 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)

5.(K690) RETURN CIRCUIT OPEN
Measure the resistance of the sensor (K690) return circuit between the
sensor harness connector and the ECM harness connector.
Is the resistance less than 10 Ohms?
Ye s>>
Go To 6
No>>
Repair 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)
6.(K615) SIGNAL CIRCUIT SHORTED
Check for a short circuit from the (K615) signal circuit to all other cir-
cuits at the ECM harness connector.
Istheresistancemorethan100kohms?
Ye s>>
Go To 7
No>>
Repair or replace the harness for a short to ground in the
signal circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)

7.ECM
Reconnect the ECM harness connector.
Turn the ignition on.
With the scan tool, erase DTCs.
While monitoring with scan tool, use a jumper wire and connect the
sensor (K615) signal circuit to the sensor (K690) return circuit at the
sensor connector.
Did the DTC P0072 set?
Ye s>>
Refer to the INTERMITTENT CONDITION Symptom (Diag-
nostic Procedure). (Refer to 9 - ENGINE - 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)
No>>
Replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

When Monitored:
Engine running.
Set Condition:
Fuel pressure is above a calibrated value for a calibrated amount of time.
Possible Causes
FUEL CONTROL ACTUATOR (FCA)
FUEL PRESSURE SENSOR
INTERMITTENT CONDITION
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.Fuel Pressure Sensor
Using the scan tool, compare the scan tool reading for fuel pressure set point to the scan tool reading for actual fuel
pressure.
Does the actual fuel pressure correlate with the fuel pressure setpoint while operating the engine over
various operating conditions?
Ye s>>
Go To 2
No>>
Check the electrical connector of the Fuel Control Actuator, if the connection is tight, replace the fuel
control actuator.
Perform POWERTRAIN VERIFICATION TEST VER - 2 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING).
2.FUEL PUMP
Turn the ignition on.
Disconnect the Electronic Fuel Control Actuator connector.
Connect an incandescent test light across the Fuel Control Actuator driver pin and the Fuel Control Actuator return
wire at the fuel control actuator connector.
Observe the test light.
The ECM will perform a self test of the circuit which should momentarily flash the test light brightly, one time,
approximately 20 seconds after being connected.
NOTE: Compare test light brightness to that of a direct connection to the battery.
Did the light flash brightly?
Ye s>>
Replace the fuel pump.
Perform POWERTRAIN VERIFICATION TEST VER - 2 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)