What is P0074 fault code? What is Ambient Air Temperature Sensing Circuit Intermittent Failure? How do I fix the P0074 fault code What are the symptoms and causes for the P0074 fault code
What is the P0074 fault code? What does it signify?
P0074 means that the ambient temperature sensor circuit is malfunctioning. A malfunction code P0074 can be triggered when the powertrain controller module (PCM), receives an intermittent signal from the sensor.
The AAT sensor converts ambient air temperature into an electrical signal and sends it back to the PCM. This information is used to adjust the operation and display the outside temperature.
In addition to the AAT sensor information, the PCM also uses information about the intake air temperature sensor (IAT) and the engine coolant temp (ECT) sensor. The AAT sensor signal is compared to the IAT or ECT signals when a cold engine starts for the first time. Even after the engine has warmed up, the PCM monitors the sensors to ensure accuracy. If the PCM detects that an intermittent voltage signal is coming from the AAT sensor, fault code P0074 can be set.
This code is most often set to indicate electrical problems. There may be different troubleshooting steps depending on the manufacturer, type of AAT sensors and wire colors.
Some vehicles are prone to P0074 fault codes, including but not limited to: Chevrolet, Audi and Porsche models, as well as Nissan, Mercedes Benz cars, Ford, Mitsubishi, Jeeps, Dodge, Chrysler, Dodge, and Suzuki.
What causes the P0074 Fault code?
Below are some reasons to set fault code P0074:
- – Defective ambient air temperature sensor (AAT)
- AAT sensor wiring – Open or Short Circuit
- – Unsold connectors or damaged, rusty wires
- – Sensor is contaminated by foreign objects
- – Defective PCM (very rare)
What are the symptoms for P0074’s Fault Code?
These symptoms may be present in vehicles with code P0074.
- – Illumination for check engine light
- – Your air conditioner might not be functioning properly
- – Incorrect readings of the interior temperature display
How do I fix the P0074 fault code?
When diagnosing code P0074, the most common error is to replace the ambient temperature sensor without first checking the wiring and connector.
There are several repairs that can resolve the P0074 fault code:
- Repair of damaged or short-circuited cables
- – Cleaning of corroded electrical circuits and connectors
- – Clean or replace the ambient temperature sensor
The Power Control Module (PCM), should be checked in rare instances. Although this is rare, it is still possible.
How serious is the Fault Code P0074?
If the code P0072 doesn’t prevent the vehicle working properly, it is not considered to be serious. In certain cases, the climate control system (heat/cold climate controls) may stop working properly. This can cause irritation depending on the weather conditions.
