DTC P0072: Ambient Temp Sensor Circuit Low: Testing
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.
- Turn ignition on, engine not running. With the DRBIII(R), read the ambient temperature sensor voltage. If the voltage below .3 volt, go to next step. If the voltage is not below .3 volt, see INTERMITTENT CONDITION under SYSTEM TESTS. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS.
- Turn the ignition off. Disconnect the ambient temperature sensor harness connector. Turn the ignition on, engine not running. With the DRBIII(R), read AAT sensor voltage. If the voltage is above 4.6 volts, replace the ambient temperature sensor. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS. If the voltage is not above 4.6 volts, go to next step.
- Turn the ignition off. Disconnect the PCM harness connectors. Measure the resistance between ground and the (G31) AAT sensor signal circuit at the AAT sensor harness connector. If the resistance is below 100 ohms, repair the short to ground in the (G31) AAT sensor signal circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS. If the resistance is not below 100 ohms, go to next step.
- Measure the resistance between the (G31) AAT sensor signal circuit and the (K4) sensor ground circuit at the AAT sensor harness connector. If the resistance is below 100 ohms, repair the short between the (K4) sensor ground circuit and the (G31) AAT sensor signal circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS. If the resistance is not below 100 ohms, go to next step.
- Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all power and ground circuits. If there are no possible causes remaining, replace and program the PCM. See PROGRAMMING . Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS.
NOTE:
Before continuing, check the PCM harness connector terminals for corrosion, damage, or pushed out terminals. Repair as necessary.