GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1998 🢒 Sonoma Pickup - 2WD 🢒 DTC 🢒 DTC B0165 Pass Compart Temp Sensor 1 Circuit Low

Object Number: 283802 Size: MF

Circuit Description

The passenger compartment temperature sensor #1 is a thermistor used to control the signal voltage in the heater and A/C control module. The heater and A/C control module supplies a reference voltage (about 5 volts) on CKT 734 to the sensor. When the inside air temperature is cold, the thermistor resistance is high. Therefore, the heater and A/C control module will receive a high voltage input. If the outside air temperature is hot, the thermistor resistance is low. Therefore, the heater and A/C control module will receive a low signal voltage input. Refer to Sensor Resistance Table .

Conditions for Setting the DTC

When the ignition is ON, the heater and A/C control module will detect the DTC B0165 any time that CKT 734 is at or near zero voltage.

Action Taken When the DTC Sets

The heater and A/C control module will use a default value of 75°F (or 88 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
    • The heater and A/C control module may set class 2 lost communication DTCs when the BCM or the VCM is being reprogrammed After reprogramming, inspect for DTCs in the heater and A/C control module. Clear any history U DTCs, then resume diagnostics.
    • Visually inspect the sensor connector and harness for corrosion and damage. The resistance value of the sensor must be 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 resistance of passenger compartment temperature sensor #1.

    2.

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

    3.

  3. This step inspects for intermittents and tests for a malfunctioning heater and A/C control module.

    4.

  4. This step repairs the short to ground in CKT 734 (DK GRN).

    5.

  5. This step replaces a defective passenger compartment temperature sensor #1.

    6.

  6. This step replaces a defective heater and A/C control module.

Step

Action

Value(s)

Yes

No

1

  1. Turn the ignition to the OFF position.
  2. Disconnect passenger compartment temperature sensor #1.
  3. Measure the resistance between passenger compartment temperature sensor terminal A and terminal D.
  4. Compare the reading to the temperature/resistance table. Refer to Sensor Resistance Table

Is the resistance within the specified range?

--

Go to Step 2

Go to Step 5

2

  1. Disconnect the heater and A/C control module.
  2. Inspect for a short to ground in CKT 734 (DK GRN) at terminal D1 of the heater and A/C control module harness connector.

Does the DMM indicate less than the specified value?

5 ohms

Go to Step 4

Go to Step 3

3

  1. Reconnect passenger compartment temperature sensor #1.
  2. Reconnect the heater and A/C control module.
  3. Turn the ignition to the ON position.
  4. Clear any heater and A/C control module DTCs.

Does the DTC reset?

--

Go to Step 6

Go to Intermittents and Poor Connections Diagnosis in Wiring Systems

4

Repair the short to ground in CKT 734 (DK GRN).

Is the repair complete?

--

Go to Diagnostic System Check

--

5

Replace passenger compartment temperature sensor #1.

Is the repair complete?

--

Go to Diagnostic System Check

--

6

Replace the heater and A/C control module.

Is the repair complete?

--

Go to Diagnostic System Check

--