For 1990-2009 cars

### Conditions for Setting the DTC

This DTC will set if the output of the ambient air temperature sensor indicates a probable short circuit or an open in the sensor or the associated wiring harness, or a malfunction of the automatic temperature control (ATC) controller.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Disconnect the ambient air sensor connector from the front bumper harness.
2. Measure the resistance between the ambient air sensor connector terminals.

Is the resistance measured equal to the specified range at 20-25°C (68-77°F)?

2600-2100 Ω

Go to Step 5

Go to Step 2

2 |

1. Remove the ambient air sensor from behind the front bumper.
2. Inspect the wiring for any open or short and examine the connector for any damage.

Is there a problem with the wiring or the connector?

--

Go to Step 3

Go to Step 4

3 | Repair the problem found in the ambient air sensor wiring or the connector. Did you complete the repair? | -- | System OK | --
4 | Replace the ambient air sensor. Did you complete the replacement? | -- | System OK | --
5 |

1. Turn the ignition to ON.
2. Measure the voltage between the 2 terminals in the ambient air sensor connector on the front bumper harness.

Is the voltage measured greater than or equal to the specified value?

4 V

Go to Step 7

Go to Step 6

6 |

1. Connect the in-car sensor to the controller.
2. Turn the ignition switch to ON.
3. Observe the temperature display area.

Does this display indicate the continuing presence of a DTC 2 condition?

--

Go to Step 8

System OK

7 |

1. Pull the automatic temperature control (ATC) controller from the instrument panel, leaving the wiring harness connected.
2. Measure the voltage between terminals A13 and B8 by backprobing the connectors.

Is the voltage measured less than or equal to the specified value?

4 V

Go to Step 8

Go to Step 9

8 | Replace the ATC controller. Did you complete the replacement? | -- | System OK | --
9 |

1. Test the wiring for the ambient air sensor from the ATC controller, through connectors C209, C208, C202 and C303 for non-diesel applications and C208, C202 and C113 for diesel applications, to the ambient air sensor connector on the front bumper harness.
2. Repair any open or high resistance condition in the wiring or a connector terminal.

Did you complete the repair?

--

System OK

--