GM Service Manual Online
For 1990-2009 cars only

Object Number: 598765  Size: SF
HVAC Components
Temperature Actuators
Temperature Controls
Handling Electrostatic Discharge Sensitive Parts Notice

Circuit Description

The heater-A/C control receives a left electric actuator position signal from the left electric actuator. The left electric actuator position sensor is a potentiometer that is tied to a 5V source through circuit 1217 (PNK/BLK) and to ground through circuit 61 (YEL) , both from the heater-A/C control. The variable output from the potentiometer feeds back a position signal through circuit 1218 (BRN/WHT) to a pull-up resistor in the heater-A/C control. This signal relates to the position of the left electric actuator. This signal is used in order to determine the necessary drive signal to the left electric actuator motor in order to provide the proper air mix door position.

Conditions for Setting the DTC

The heater-A/C control performs an internal check on the left electric actuator position and determines the left electric actuator is out of range.

Action Taken When the DTC Sets

The heater-A/C control stores DTC B0441 in memory.

Conditions for Clearing the DTC

    • 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 will clear after 100 drive cycles if the condition for this malfunction is no longer present.
    • Using a scan tool

Diagnostic Aids

The following conditions may cause DTC B0441 to set:

    • A voltage spike in circuit 1218 (BRN/WHT)
    • A short to ground in circuit 1217 (PNK/BLK)
    • A short to B+ in circuit 1218 (BRN/WHT)
    • An open in circuit 61 (YEL), circuit 1217 (PNK/BLK) or circuit 1218 (BRN/WHT)

Test Description

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

  1. This test checks if the heater-A/C control 5V supply is getting through circuit 1217(PNK/BLK).

  2. This test checks if the heater-A/C control 5V supply is getting through circuit 1218 (BRN/WHT).

  3. This test checks if the heater-A/C control ground is getting through circuit 61(YEL).

Step

Action

Value(s)

Yes

No

1

Was the heater-A/C control diagnostic system check performed?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Turn the ignition switch off.
  2. Disconnect the LH electric actuator electrical connector.
  3. Start the engine.
  4. Set the heater-A/C control to AUTO, and temperature at 16°C (60°F)
  5. Use a digital multimeter (DMM) to measure the voltage between the LH electric actuator harness connector terminal 10 and ground.

Is the measured voltage within the specified range?

4.5-5.5V

Go to Step 3

Go to Step 5

3

Use a DMM, measure the voltage between the LH electric actuator harness connector terminal 7 and terminal  10.

Is the measured voltage within the specified range?

4.5-5.5V

Go to Step 4

Go to Step 8

4

Using a DMM to measure the voltage between the LH electric actuator harness connector terminal 9 and ground.

Is the measured voltage within the specified range?

4.5-5.5V

Go to Step 12

Go to Step 9

5

Check circuit 1217 (PNK/BLK) for a short to ground. Refer to Circuit Testing in Wiring Systems.

Is there a short to ground in circuit 1217 (PNK/BLK) ?

--

Go to Step 6

Go to Step 7

6

Locate and repair a short to ground in circuit 1217 (PNK/BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 13

--

7

  1. Check for a poor connection or open in circuit 1217 (PNK/BLK). Refer to Testing for Intermittent Conditions and Poor Connections and Circuit Testing in Wiring Systems.
  2. Replace the heater-A/C control if circuit 1217 (PNK/BLK) is OK. Refer to Control Assembly Replacement

Is the repair complete?

--

Go to Step 13

--

8

  1. Check for a poor connection or open in circuit 61(YEL). Refer to Testing for Intermittent Conditions and Poor Connections and Circuit Testing in Wiring Systems.
  2. Replace the heater-A/C control if circuit 61 (YEL) is OK. Refer to Control Assembly Replacement

Is the repair complete?

--

Go to Step 13

--

9

Check circuit 1218 (BRN/WHT) for a short to B+ or short to ground. Refer to Circuit Testing in Wiring Systems.

Is there a short to B+ or short to ground in circuit 1218 (BRN/WHT) ?

--

Go to Step 10

Go to Step 11

10

Locate and repair a short to B+ or short to ground in circuit 1218 (BRN/WHT). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 13

--

11

  1. Check for a poor connection or open in circuit 1218 (BRN/WHT). Refer to Testing for Intermittent Conditions and Poor Connections and Circuit Testing in Wiring Systems.
  2. Replace the heater-A/C control if circuit 1218 (BRN/WHT) is OK . Refer to Control Assembly Replacement

Is the repair complete?

--

Go to Step 13

--

12

Replace the LH electric actuator. Refer to Temperature Actuator Replacement (LH) .

Is the repair complete?

--

Go to Step 13

--

13

Verify that the system operates properly.

Does the system operate properly?

--

System OK

Go to Diagnostic System Check