GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2009 🢒 Vibe - AWD 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC B1412

Circuit Description

The ambient temperature sensor is installed in front of the condenser. The ambient temperature sensor detects the temperature outside the cabin based on changes in the resistance of its built-in thermistor and sends the appropriate signals to the A/C amplifier via the CAN communication system.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1412 Ambient Temperature Sensor Circuit

Conditions for Running the DTC

This DTC shall run when the ignition is On.

Conditions for Setting the DTC

An open or short in the ambient temperature sensor circuit.

Action Taken When the DTC Sets

The A/C compressor will be disabled.

Conditions for Clearing the DTC

The DTC will clear when conditions for setting the DTC have been repaired.

Step

Action

Value(s)

Yes

No

Schematic Reference: HVAC Schematics

Connector End View Reference: Component Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With the scan tool, observe the Outside Air Temp Sensor parameter in the HVAC data list.

Does the Outside Air Temp parameter display the current ambient temperature?

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Go to Step 3

Go to Step 7

3

  1. Turn OFF ignition.
  2. Disconnect the instrument panel harness connector.
  3. Measure the resistance between connector E46 terminal 9 and terminal 23 at 25°C (77°F) and at 40°C (104°F).

Is the resistance measured within the specified values?

25°C (77°F) = 1.6 - 1.8 Kohms

40°C (104°F) = 0.8 - 1.0 Kohms

Go to Step 4

Go to Step 5

4
  1. Replace the instrument cluster with a known good one.
  2. With the scan tool, check to see if DTC resets.

Does DTC reset?

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Go to Step 7

Go to Step 9

5
  1. Remove the ambient temperature sensor.
  2. Measure the resistance between connector A23 terminal 1 and terminal 2 at 10°C (50°F), 15°C (59°F), 20°C (68°F), 25°C (77°F), 30°C (86°F), 35°C (95°F), 40°C (104°F), 45°C (113°F), 50°C (122°F), 55°C (131°F) and at 60°C (140°F).

Does the resistance measure within the specified values?

10°C (50°F) = 3 - 3.75 Kohms

15°C (59°F) = 2.45 - 2.88 Kohms

20°C (68°F) = 1.95 - 2.30 Kohms

25°C (77°F) = 1.60 - 1.80 Kohms

30°C (86°F) = 1.28 - 1.47 Kohms

35°C (95°F) = 1.00 - 1.22 Kohms

40°C (104°F) = 0.80 - 1.00 Kohms

45°C (113°F) = 0.65 - 0.85 Kohms

50°C (122°F) = 0.50 - 0.70 Kohms

55°C (131°F) = 0.44 - 0.60 Kohms

60°C (140°F) = 0.36 - 0.50 Kohms

Go to Step 6

Go to Step 8

6

Repair or replace harness or connector between the ambient temperature sensor and instrument panel.

Did you complete the repair or replacement?

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Go to Step 10

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7

Replace the air conditioning amplifier.

Did you complete the replacement?

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Go to Step 10

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8

Replace the ambient temperature sensor.

Did you complete the replacement?

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Go to Step 10

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9

Replace the instrument cluster. Refer to Instrument Cluster Replacement.

Did you complete the replacement?

 

Go to Step 10

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10
  1. Use the scan tool in order to clear the DTC.
  2. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.

Does the DTC reset?

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Go to Step 2

System OK