P00DC

P00DC-AMBIENT AIR TEMPERATURE SENSOR CIRCUIT HIGH





For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Diesel Exhaust Fluid (DEF) Ambient Air Temperature Sensor is mounted to the DEF Supply Pump Assembly bracket. The Powertrain Control Module provides a 5-Volt Signal and a sensor ground circuit for the DEF Ambient Air Temperature Sensor. The DEF Ambient Air Temperature Sensor signal is provided to the DEF Dosing Control Unit via the PCM. The DEF Dosing Control Unit uses this information along with the diesel exhaust fluid temperature information to determine if the Selective Catalytic Reduction (SCR) system is required.

- When Monitored:
With the ignition on.

- Set Condition:
The Powertrain Control Module detects that the DEF Ambient Air Temperature Sensor is above 4.8 Volts for one second.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. ACTIVE DTC

NOTE: If there are any 5-Volt supply DTCs present, repair those DTCs before proceeding with this test.

1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 75 seconds.
5. Turn the ignition on.
6. With the scan tool, read DTCs.

Did the DTC return?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION - 6.7L diagnostic procedure. . Intermittent Condition Test

2. CHECK THE (G32) DEF AMBIENT AIR TEMPERATURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
1. Disconnect the DEF Ambient Air Temperature Sensor harness connector.

NOTE: Check connectors - Clean/repair as necessary.

2. With a voltmeter connected to ground, measure the voltage of the (G32) DEF Ambient Air Temperature Sensor Signal circuit at the DEF Ambient Air Temperature Sensor harness connector.

Does the voltage measure above 5.1 Volts?

Yes

- Repair the (G32) DEF Ambient Air Temperature Sensor Signal circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 3

3. CHECK THE DEF AMBIENT AIR TEMPERATURE SENSOR
1. With the scan tool, erase DTCs.
2. While monitoring with scan tool, use a jumper and connect the DEF Ambient Air Temperature Sensor Signal circuit to the DEF Ambient Air Temperature Sensor Ground circuit at the DEF Ambient Air Temperature Sensor harness connector.

NOTE: Be careful not to spread the terminals.

Did the DTC P00DB-DEF AMBIENT AIR TEMPERATURE SENSOR LOW set as active or pending?

Yes

- Replace the DEF Ambient Air Temperature Sensor. Diesel Exhaust Fluid Ambient Temperature Sensor - Removal.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 4

4. CHECK THE (G32) DEF AMBIENT AIR TEMPERATURE SENSOR SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE




1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance of the (G32) DEF Ambient Air Temperature Sensor Signal circuit between the DEF Ambient Air Temperature Sensor harness connector and the PCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 5

No

- Repair the (G32) DEF Ambient Air Temperature Sensor Signal circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

5. CHECK THE (K900) DEF AMBIENT AIR TEMPERATURE SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE




1. Measure the resistance of the (K900) DEF Ambient Air Temperature Sensor Ground circuit between the DEF Ambient Air Temperature Sensor harness connector and the PCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Replace the Powertrain Control Module. . Powertrain Control Module - Removal
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Repair the (K900) DEF Ambient Air Temperature Sensor Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.