GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Blazer - 4WD - RHD 🢒 DTC 🢒 DTC B0160 Outside Air Temp Sensor Circuit Low

Object Number: 569104 Size: MF
HVAC Components
ECC Module and Temperature Sensors
Handling ESD Sensitive Parts Notice
DTC B0165, B0166, B0180, B0181, B0185, B0186 Thumbnail
DTC B0165, B0166, B0180, B0181, B0185, B0186 Thumbnail
DTC B0165, B0166, B0180, B0181, B0185, B0186 Thumbnail

Circuit Description

The outside air temperature sensor is a thermistor used to control the signal voltage in the electronic climate control module. The electronic climate control module supplies a reference voltage (about 5 volts) on CKT 636 (DK GRN/WHT) to the sensor. When the outside (ambient) air temperature is cold, the thermistor resistance is high. Therefore, the electronic climate control module will receive a high voltage input. If the outside air temperature is hot, the thermistor resistance is low. The electronic climate control module will receive a low signal voltage input. Refer to Sensor Resistance Table .

Conditions for Setting the DTC

When the ignition switch is in the ON position, the electronic climate control module will detect this DTC any time CKT 636 (DK GRN/WHT) is at or near zero voltage.

Action Taken When the DTC Sets

The electronic climate control module will use a default value of -3.3°C (26°F) (or 168 A/D counts) until the fault is cleared.

Conditions for Clearing the MIL/DTC

This fault will clear as soon as the fault goes away or has been repaired. The system will then return to normal operation. History DTCs can only be cleared by removing and restoring B+ or by using the scan tool.

Diagnostic Aids

Visually inspect the sensor connector and harness for corrosion and damage. The resistance value of the sensor must be within 300-170,000 ohms. If resistance is not within specifications, replace the sensor.

Test Description

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

  1. This step measures the resistance of the outside (ambient) air temperature sensor.

    2.

  2. This step inspects for a short to ground in CKT 636 (DK GRN/WHT).

    3.

  3. This step inspects for intermittents and tests for a malfunctioning electronic climate control module.

    4.

  4. This step repairs the short to ground in CKT 636 (DK GRN/WHT).

    5.

  5. This step replaces a defective outside (ambient) air temperature sensor.

    6.

  6. This step replaces a defective electronic climate control module.

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the outside (ambient) air temperature sensor.
  3. Measure the resistance between sensor terminal A and terminal B.
  4. Compare the reading to the temperature/resistance table. Refer to Sensor Resistance Table .

Is the resistance within the range specified in the table?

--

Go to Step 3

Go to Step 6

3

  1. Disconnect the electronic climate control module.
  2. Inspect for a short to ground in CKT 636 (DK GRN/WHT) at terminal D2 of the electronic climate control module harness connector.

Is continuity present?

--

Go to Step 5

Go to Step 4

4

  1. Reconnect the sensor.
  2. Reconnect the electronic climate control module.
  3. Turn the ignition switch to the ON position.
  4. Clear any electronic climate control module DTCs.

Does the DTC reset?

--

Go to Step 7

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

5

Repair the short to ground in CKT 636 (DK GRN/WHT).

Is the repair complete?

--

Go to Diagnostic System Check

--

6

Replace the outside air temperature sensor.

Is the replacement complete?

--

Go to Diagnostic System Check

--

7

Replace the electronic climate control module.

Is the replacement complete?

--

Go to Diagnostic System Check

--