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DTC P0071: Ambient Temperature Sensor Performance: Testing

WARNING: This page is about a different car, the 2004 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition on, engine not running. With the DRBIII(R), read DTCs and record the related Freeze Frame data. If the Good Trip Counter displayed and equal to zero, go to next step. If the Good Trip Counter is not displayed or equal to zero, see INTERMITTENT CONDITIONS  . Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  .
    2. NOTE: Visually inspect both the component and the PCM connectors. Look for damage, partially broken wires and backed out or corroded terminals.
  2. Turn the ignition off. Disconnect the Ambient Air Temp Sensor harness connector. Turn the ignition on, engine not running. Measure the voltage of the (K25) AAT Signal circuit in the Ambient Air Temperature Sensor harness connector. If the voltage is above 5.2 volts, repair the short to battery voltage in the (K25) AAT Signal circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  . If the voltage is not above 5.2 volts, go to next step.
  3. Turn the ignition off. Disconnect the Ambient Air Temperature Sensor harness connector. Turn the ignition on, engine not running. With the DRBIII(R), read the Ambient Air Temperature Sensor voltage. If the voltage is above 4.9 volts, go to next step. If the voltage is not above 4.9 volts, go to step  7 .
  4. Turn the ignition off. Disconnect the Ambient Air Temperature Sensor harness connector. Using a jumper wire, jumper across the Ambient Air Temperature Sensor harness connector. Turn the ignition on, engine not running. With the DRBIII(R), read the Ambient Air Temperature voltage. If the voltage is below 1.0 volt, replace the Ambient Air Temperature Sensor. Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  . If the voltage is not below 1.0 volt, go to next step.
    5. CAUTION: DO NOT probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool (8815) to perform diagnosis.
  5. Turn the ignition off. Disconnect the Ambient Air Temperature Sensor harness connector. Disconnect the PCM harness connector. Measure the resistance of the (K25) AAT Signal circuit from the Ambient Air Temperature Sensor harness connector to the appropriate terminal of Miller Special Tool (8815). If the resistance is below 5.0 ohms, go to next step. If the resistance is not below 5.0 ohms, repair the open in the (K25) AAT Signal circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  .
    6. CAUTION: DO NOT probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool (8815) to perform diagnosis.
  6. Turn the ignition off. Disconnect the Ambient Air Temperature Sensor harness connector. Disconnect the PCM harness connector. Measure the resistance of the (K167) Sensor ground circuit from the Ambient Air Temperature Sensor harness connector to the appropriate terminal of Miller Special Tool (8815). Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. If the resistance below 5.0 ohms, repair as necessary. Replace and program the Powertrain Control Module. See PROGRAMMING  . Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  . If the resistance is not below 5 ohms, repair the open in the (K4) Sensor ground circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  .
  7. Turn the ignition off. Disconnect the Ambient Air Temperature Sensor harness connector. Disconnect the PCM harness connector. Measure the resistance between ground and the (K25) AAT Signal circuit. If the resistance is below 100 ohms, repair the short to ground in the (K25) AAT Signal circuit. Turn the ignition off. Disconnect the Ambient Air Temperature Sensor harness connector. Disconnect the PCM harness connector. Measure the resistance between ground and the (K25) AAT Signal circuit. If the resistance is below 100 ohms, repair the short to ground in the (K25) AAT Signal circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  . If the resistance is not below 100 ohms, go to next step.
  8. Turn the ignition off. Disconnect the Ambient Air Temperature Sensor harness connector. Disconnect the PCM harness connector. Measure the resistance between the (K25) AAT Signal circuit and the (K4) Sensor ground circuit in the Ambient Air Temperature Sensor harness connector. If the resistance is below 100 ohms, repair the Sensor ground shorted to the (K25) AAT Signal circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  . Before continuing, check the PCM harness connector terminals for corrosion, damage or terminal push out. Repair as necessary. If the resistance is not below 100 ohms, replace and program the Powertrain Control Module. See PROGRAMMING  . Perform POWERTRAIN VERIFICATION TEST VER-5 (NGC)  .
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