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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2000 🢒 Intrigue 🢒 HVAC 🢒 HVAC Systems - Automatic 🢒 DTC B0337 Inside Air Temp Sensor Short to GND

Object Number: 598760 Size: MF
HVAC Components
Inputs
Inputs
Handling Electrostatic Discharge Sensitive Parts Notice

Circuit Description

The heater-A/C control determines the inside air temperature through an input from the inside air temperature sensor. The heater-A/C control receives a voltage signal from the inside air temperature sensor through circuit 734 (DK GRN). The inside air temperature sensor is grounded by the heater-A/C control through circuit 61 (YEL).

The internal resistance of the inside air temperature sensor decreases as the temperature increases. The difference between the ambient air temperature sensor and the inside air temperature sensor measurements is used by the heater-A/C control in order to determine whether the incoming air should be cooled or warmed, and to what degree, in order to bring the inside air temperature to the selected temperature as quickly as possible.

Conditions for Setting the DTC

The heater-A/C control performs a check on the operation of the inside air temperature sensor and detects a short to ground in circuit 734 (DK GRN).

Action Taken When the DTC Sets
    • The heater-A/C control stores DTC B0337 in memory.
    • The heater-A/C control uses 24°C (75°F) as a substitute for the inside air temperature reading , allowing the A/C system to continue operation.

Conditions for Clearing the DTC
    • A short to ground in circuit 734 (DK GRN) is no longer present.
    • Under all fault conditions, the ignition switch must be cycled from on to off, back to on before this DTC can change from current to history.
    • A history DTC clears after 100 drive cycles if a short to ground in circuit 734 (DK GRN) is no longer present.
    • Using a scan tool

Diagnostic Aids

The following conditions may cause this DTC to set:

    • A short to ground in circuit 734 (DK GRN)
    • A voltage spike in circuit 734 (DK GRN)
    • A faulty inside air temperature sensor
    • A faulty heater-A/C control

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step checks for proper voltage value at the inside air temperature sensor.

    2.

  2. This step checks for a short to ground in 734 (DK GRN) .

Step

Action

Value(s)

Yes

No

1

Did you perform the heater-A/C control diagnostic system check?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Turn the ignition switch off.
  2. Disconnect the inside air temperature sensor connector.
  3. Turn the ignition switch on.
  4. Set the heater-A/C control in the AUTO position.
  5. Use a digital multimeter (DMM) to measure the voltage between the inside air temperature sensor harness connector terminal A and ground.

Is the measured voltage within the specified value?

4.5-5.5V

Go to Step 3

Go to Step 4

3
  1. Inspect the inside air temperature sensor connector for poor or dirty terminal contact. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
  2. Replace the inside air temperature sensor If the connection is OK . Refer to Inside Air Temperature Sensor Replacement .

Is the repair complete?

--

Go to Step 7

--

4

  1. Turn the ignition switch off.
  2. Disconnect the heater-A/C control connector.
  3. Use a DMM to measure the resistance between heater-A/C control harness connector terminal D2 (CKT 734) and ground.

Is the measured resistance same as the specified value?

∞

Go to Step 6

Go to Step 5

5

Locate and repair a short to ground in circuit 734 (DK GRN). Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 7

--

6

Replace the heater-A/C control. Refer to Control Assembly Replacement .

Is the repair complete?

--

Go to Step 7

--

7

Verify the operation of the system.

Does the system operate properly?

--

System OK

Go to Diagnostic System Check