P00DA

P00DA-AMBIENT AIR TEMPERATURE SENSOR CIRCUIT PERFORMANCE





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 when the DEF System heaters need to be turned on. The PCM will turn on the MIL Lamp immediately after the monitor runs and fails and the PCM will substitute a default value for the DEF Ambient Air Temperature Sensor.

- When Monitored:
There are two for this DTC. The first monitor runs at initial key on after an eight hours cold soak. The DEF Ambient Air Temperature Sensor is compared to the other temperature sensors. The second monitor runs after the engine is running. The PCM looks for a change in temperature over time.

- Set Condition:
The Powertrain Control Module (PCM) detects that the DEF Ambient Air Temperature Sensor is out of range as compared to the other temperature sensors at key on or is not changing over time.





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, read DTCs.

Is the DTC active?

Yes

- Go To 2

No

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

2. CHECK THE DEF AMBIENT AIR TEMPERATURE SENSOR
1. With the scan tool, erase DTCs.
2. Turn the ignition off.
3. Disconnect the DEF Ambient Air Temperature Sensor harness connector.
4. Turn the ignition on and wait 30 seconds while monitoring the scan tool.
5. 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 and monitor the scan tool for 30 seconds.

Did the P00DC-DEF AMBIENT AIR TEMPERATURE SENSOR HIGH set with the sensor disconnected and the P00DB-DEF AMBIENT AIR TEMPERATURE SENSOR LOW set with the jumper in place?

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 3

3. 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 4

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.

4. 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.