GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Park Avenue 🢒 DTC 🢒 DTC 1310 Outside Air Temperature Sensor Fault

Object Number: 390975 Size: MF
HVAC Components
HVAC Air Delivery/Temperature Control Schematics
Handling ESD Sensitive Parts Notice
Cell 68: Temperature Sensors

Circuit Description

The Ambient Air Temperature Sensor is a thermistor that controls signal voltage to the Heater Control Module (HCM). The HCM supplies voltage on circuit 735. When the sensor is cold, the resistance is high and the HCM will sense a high signal voltage at terminal B1, connector C2. When the sensor warms, resistance is reduced and the signal voltage is pulled low through circuit 61. Signal voltage will vary from 5 V (open circuit) to 0 V (short circuit).

Conditions for Setting the DTC
    • The ignition is ON.
    • Circuit open or shorted.

Action Taken When the DTC Sets
    • A blank is displayed on the drivers information center.
    • A default value of 15°C (59°F) will be used by the HCM to allow operation of the A/C system.

Conditions for Clearing the DTC
    • Using a Scan Tool .
    • A history DTC will clear after 50 fault free ignition cycles.
    • HCM battery voltage is interrupted.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Perform the Body Control Module Diagnostic System Check before continuing with the diagnosis of this DTC.

    2.

  2. Ensures that the DTC was not set in error.

    3.

  3. Determines whether the malfunction is the sensor or if there is an open or a short in a circuit.

    4.

  4. Determines if the HCM is malfunctioning.

    5.

  5. TheScan Tool checks for proper sensor operation. Clear all DTCs after the repair procedures are complete.

DTC 1310 Ambient Air Temperature Sensor

Step

Action

Value(s)

Yes

No

1

Was the BCM diagnostic system check performed?

--

Go to Step 2

Go to Diagnostic System Check - Body Control System

2
  1. Turn the ignition ON.
  2. Measure the voltage between sensor harness connector terminals A and B.

Refer to Measuring Voltage in Wiring Systems.

Is the specified voltage measured?

4.5-5.5 V

Go to Step 3

Go to Step 4

3

  1. Turn the ignition OFF.
  2. Reconnect the sensor.
  3. Connect the Scan Tool .
  4. Turn the ignition ON.
  5. Clear the DTC using Scan Tool .
  6. Start the engine.

Did the DTC reset?

--

Go to Step 4

Go to Intermittents and Poor Connections

4

  1. Connect the Scan Tool .
  2. Select HCM open/short data.
  3. Display ambient air temperature data.
  4. Start the engine.
  5. Unplug the ambient temperature sensor.
  6. The ambient temperature sensor voltage increases to 5 V
  7. Reconnect the ambient temperature sensor connector.

Did the ambient temperature sensor voltage decrease?

--

Go to Step 5

Go to Step 6

5

Replace the sensor.

Refer to Ambient Temperature Sensor Replacement

Is the replacement complete?

--

Go to Step 9

--

6

Inspect CK 61 (YEL) for an open or short.

Was an open or short located?

--

Go to Step 8

Go to Step 7

7

  1. Inspect CKT 735 (LT GRN/BLK) for an open or short.
  2. If OK, replace the HCM. Refer to Programmer Replacement Programmer Replacement

Is the replacement complete?

--

Go to Step 9

--

8

Repair open in CKT 61 (YEL),

Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 9

--

9

  1. Using the Scan Tool clear all the DTCs.
  2. Confirm proper operation of the A/C system.

Is the A/C system operating normally?

--

Go to Diagnostic System Check - Body Control System

--