Ambient Temperature Sensor: Notes
WARNING: This page is about a different car, the 2004 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
The ambient air temperature is monitored by the PCM and is displayed by the CMTC. The PCM receives a hardwire input from the ambient temperature sensor (ATS).
The ATS is a variable resistor that operates on a 5-volt reference signal circuit hardwired from the PCM. The resistance in the ATS changes as the outside temperature rises or falls. The PCM senses the change in reference voltage through the ATS resistor. Based on the resistance of the ATS, the PCM is programmed to correspond to a specific temperature. The PCM stores and filters the ambient temperature data and transmits this data to the CMTC via the PCI Bus. The ATS cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.