Recently pulled this code (P0072-AMBIENT TEMP SENSOR LOW), any one know what to do to fix this. I need to fix it asap as I will be needing to get my inspection sticker and will be going on a trip next week. Thanks

 

POSSIBLE CAUSES

AMBIENT AIR TEMPERATURE SENSOR VOLTAGE BELOW .04 VOLTS
AMBIENT AIR TEMPERATURE SENSOR INTERNAL FAILURE
(K145) AAT SIGNAL CIRCUIT SHORTED TO GROUND
(K145) AAT SIGNAL CIRCUIT SHORTED TO (K4) SENSOR GROUND CIRCUIT
PCM

Looks like your best bet will be to replace the sensor after checking the wiring to make sure nothing is nicked, corroded, etc...

 

you by chance know where it is located?

 

 

AMBIENT TEMPERATURE SENSOR DESCRIPTION

Ambient air temperature is monitored by the Compass Temperature Mirror through a PCI databus message from the NGC engine controller. The ambient temperature sensor is the source for the NGC engine controller. The sensor is a variable resistor mounted in front the radiator, behind the grille, near the left lower side of the radiator support assembly.

For complete circuit diagrams, refer to the appropriate wiring information. The ambient temperature sensor cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.

OPERATION
The ambient temperature sensor is a variable resistor that operates on a five-volt reference signal sent to it by the NGC engine controller. The resistance in the sensor changes as temperature changes, changing the temperature sensor signal circuit voltage to the NGC engine controller. Based upon the resistance in the sensor, the mirror senses a specific voltage on the temperature sensor signal circuit, which it is programmed to correspond to a specific temperature.

DIAGNOSIS AND TESTING - AMBIENT TEMPERATURE SENSOR
The ambient temperature sensor can be diagnosed using the following Sensor Test, and Sensor Circuit Test. If the temperature sensor and circuit are confirmed to be OK, but the temperature display is inoperative or incorrect, replace the compass/temperature display.

SENSOR TESTING
(1) Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Disconnect the ambient temperature sensor wire harness connector.
(2) Measure the resistance of the ambient temperature sensor. At room temperature (approx. 68°F), the sensor resistance should be between 9-11 Kilohms (9000-11000 ohms). The sensor resistance should read between these two values. If OK, refer to Sensor Circuit Testing below. If not OK, replace the faulty ambient temperature sensor.

SENSOR CIRCUIT TESTING
(1) Turn the ignition switch to the OFF position. Disconnect and isolate the battery negative cable. Disconnect the ambient temperature sensor wire harness connector and the NGC engine controller wire harness connector.
(2) Connect a jumper wire between the two terminals in the body half of the ambient temperature sensor wire harness connector.
(3) Check for continuity between the sensor return circuit and the ambient temperature sensor signal circuit cavities of the NGC engine controller wire harness connector. There should be continuity. If OK, go to Step 4. If not OK, repair the open sensor return circuit or ambient temperature sensor signal circuit to the ambient temperature sensor as required.
(4) Remove the jumper wire from the body half of the ambient temperature sensor wire harness connector. Check for continuity between the sensor return circuit cavity of the NGC engine controller wire harness connector and a good ground. There should be no continuity. If OK, replace the compass/ temperature display unit. If not OK, repair the shorted sensor return circuit as required.

REMOVAL
(1) Open hood, disconnect and isolate the negative battery cable.
(2) Working in the front of the vehicle, reach through the lower opening in the front fascia to access the ambient temperature sensor.
(3) Remove the ambient temperature sensor from the radiator closure panel (Fig. 4).
(4) Disconnect the ambient temperature sensor electrical connector.
(5) Remove the ambient temperature sensor from the vehicle.

INSTALLATION
(1) Working in the front of the vehicle, reach through the lower opening in the front fascia to connect the ambient temperature sensor electrical connector.
(2) Position the ambient temperature sensor and install in radiator closure panel.
(3) Connect the negative battery cable.

 

This was some good info. I got a code P0071 & needed to know where it was. I ran a deer over last year & that code popped up today. It might be the wires or it could be the sensor. So I got some checking to do tomorrow.

 

(2) Connect a jumper wire between the two terminals in the body half of the ambient temperature sensor wire harness connector.

i connected jumper wire between the two terminals without disconnecting the battery neg cable, after that i pulled the code p0072/p0073 now what to do?

please help i know what i did was idiot idea but i followed someone else advice to fix the overhead temp console stuck at -40.

hope you could give me some guides.

Thanks

Wely