GM Service Manual Online
For 1990-2009 cars only

Temperature Actuator Inoperative Buick

Step

Action

Value(s)

Yes

No

1

  1. Set the ignition switch to RUN.
  2. Remove the instrument panel compartment. Refer to Instrument Panel Storage Compartment Replacement in Instrument Panel, Gauges and Console.
  3. Move the temperature selector from "Full Cool" to "Full Hot".
  4. As you move the selector, observe the A/C temperature valve actuator arm.
  5. Compare the movement to an operational vehicle, if possible.

Does the A/C temperature valve actuator arm make a complete travel?

--

Go to Step 2

Go to Step 3

2

  1. Set the ignition switch to OFF.
  2. Refer to Temperature Valve Link Adjustment .

Does insufficient cooling and heating still exist?

--

Go to Heating Insufficient and Cooling Insufficient - Air Conditioning (A/C) Inoperative

System OK

3

  1. Set the ignition switch to OFF.
  2. Remove the temperature link rod from the temperature valve (snap out).
  3. Manually move the temperature valve to the right and to the left.

Does the temperature valve move right and left without sticking or binding?

--

Go to Step 4

Go to Step 5

4

  1. Set the ignition switch to OFF.
  2. Disconnect the HVAC control assembly connector C2.
  3. Set the ignition switch to RUN.
  4. Measure the voltage between the HVAC control assembly connector C2 terminal A8 and ground. Refer to Measuring Voltage and Troubleshooting with a Digital Multimeter in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 6

Go to Step 7

5

Replace the temperature valve. Refer to Temperature Actuator Replacement .

Is the repair complete?

--

System OK

--

6

Measure the voltage between HVAC control assembly connector C2 terminal A8 and connector C1 terminal A7. Refer to Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 9

Go to Step 10

7

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1141 (BRN) for an open or short to ground.
  3. Inspect the instrument panel fuse block fuse 5A.

Did you find an open, short, or bad fuse?

--

Go to Step 8

--

8

Repair the open, short, or bad fuse. Refer to Wiring Repairs .

Is the repair complete?

--

System OK

--

9

  1. Set the ignition switch to OFF.
  2. Inspect the HVAC control assembly connector C1 and connector C2 for proper terminal contact.

Is the terminal contact OK?

--

Go to Step 11

Go to Intermittents and Poor Connections Diagnosis

10

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1250 (BLK) for an open.
  3. If you find an open, repair the open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

11

  1. Reconnect the HVAC control assembly connector C1 and connector C2.
  2. Disconnect the A/C temperature valve actuator connector.
  3. Turn the ignition switch to RUN.
  4. Measure the voltage between A/C temperature valve actuator connector terminal 10 and ground. Refer to Measuring Voltage and Troubleshooting with a Digital Multimeter in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 12

Go to Step 13

12

Measure the voltage between A/C temperature valve actuator connector terminal 10 and terminal 7. Refer to Troubleshooting with a Digital Multimeter in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 14

Go to Step 15

13

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1141 (BRN) for an open.
  3. If you find an open, repair the open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

14

  1. Move the temperature selector from "Full Cool" to "Full Warm."
  2. As you move the selector, measure the voltage between A/C temperature valve actuator connector terminal 8 and terminal 7.

Does the measured voltage vary within the specified range?

1 V (Full Cool) - 12 V (Full Warm)

Go to Step 16

Go to Step 17

15

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1791 (YEL) for an open or short to ground.
  3. Inspect the in-line connector C200 terminal K9 for proper terminal contact.
  4. If CKT 1791 and connector C200 are both OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

16

  1. Set the ignition switch to OFF.
  2. Inspect the A/C temperature valve actuator connector for proper terminal contact.
  3. If the connector is OK, replace the A/C temperature valve actuator. Refer to Temperature Actuator Replacement .

Is the repair complete?

--

System OK

--

17

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1199 (DK BLU) for an open.
  3. Inspect the in-line connector C200 terminal K10 for proper terminal contact.
  4. If CKT 1199 and connector C200 are both OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

Temperature Actuator Inoperative Oldsmobile

Step

Action

Value(s)

Yes

No

1

  1. Set the ignition switch to RUN.
  2. Remove the instrument panel compartment. Refer to Instrument Panel Storage Compartment Replacement .
  3. Move the temperature selector from "Full Cool" to "Full Hot".
  4. As you move the selector, observe the A/C temperature valve actuator arm.
  5. Compare the movement to an operational vehicle, if possible.

Does the A/C temperature valve actuator arm make a complete travel?

--

Go to Step 2

Go to Step 3

2

  1. Set the ignition switch to OFF.
  2. Refer to Temperature Valve Link Adjustment .

Does insufficient cooling and heating still exist?

--

Go to Heating Insufficient and Cooling Insufficient - Air Conditioning (A/C) Inoperative

System OK

3

  1. Set the ignition switch to OFF.
  2. Remove the temperature link rod from the temperature valve (snap out).
  3. Manually move the temperature valve to the right and to the left.

Does the temperature valve move right and left without sticking or binding?

--

Go to Step 4

Go to Step 5

4

  1. Set the ignition switch to OFF.
  2. Disconnect the HVAC control assembly connector C2.
  3. Set the ignition switch to RUN.
  4. Measure the voltage between HVAC control assembly connector C2 terminal B and ground. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 6

Go to Step 7

5

Replace the temperature valve. Refer to Temperature Actuator Replacement .

Is the repair complete?

--

System OK

--

6

Measure the voltage between HVAC control assembly connector C2 terminal B and connector C1 terminal B. Refer to Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 9

Go to Step 10

7

  1. Set the ignition switch to OFF.
  2. Inspect CKT 41 (BRN) for an open or short to ground.
  3. Inspect the instrument panel fuse block fuse 5D.

Did you find an open, short, or bad fuse?

--

Go to Step 8

--

8

Repair the open, short, or bad fuse. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

9

  1. Set the ignition switch to OFF.
  2. Inspect HVAC control assembly connector C1 and connector C2 for proper terminal contact.

Is the terminal contact OK?

--

Go to Step 11

Go to Intermittents and Poor Connections

10

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1250 (BLK) for an open.
  3. If you find an open, repair the open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

11

  1. Reconnect the HVAC control assembly connector C1 and connector C2.
  2. Disconnect the A/C temperature valve actuator connector.
  3. Turn the ignition switch to RUN.
  4. Measure the voltage between A/C temperature valve actuator connector terminal 10 and ground. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 12

Go to Step 13

12

Measure the voltage between A/C temperature valve actuator connector terminal 10 and terminal 7. Refer to Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 14

Go to Step 15

13

  1. Set the ignition switch to OFF.
  2. Inspect CKT 41 (BRN) for an open.
  3. If you find an open, repair the open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

14

  1. Move the temperature selector from "Full Cool" to "Full Warm."
  2. As you move the selector, measure the voltage between A/C temperature valve actuator connector terminal 8 and terminal 7. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage vary within the specified range?

1 V (Full Cool) - 12 V (Full Warm)

Go to Step 16

Go to Step 17

15

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1791 (YEL) for an open or short to ground.
  3. Inspect the in-line connector C200 terminal K9 for proper terminal contact.
  4. If CKT 1791 and connector C200 are both OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

16

  1. Set the ignition switch to OFF.
  2. Inspect the A/C temperature valve actuator connector for proper terminal contact.
  3. If the connector is OK, replace the A/C temperature valve actuator. Refer to Temperature Actuator Replacement .

Is the repair complete?

--

System OK

--

17

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1199 (DK BLU) for an open.
  3. Inspect the in-line connector C200 terminal K10 for proper terminal contact.
  4. If CKT 1199 and connector C200 are both OK, replace the HVAC control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

Temperature Actuator Inoperative Pontiac

Step

Action

Value(s)

Yes

No

1

  1. Set the ignition switch to RUN.
  2. Remove the instrument panel compartment. Refer to Instrument Panel Storage Compartment Replacement in Instrument Panel, Gauges and Console.
  3. Move the temperature selector from "Full Cool" to "Full Hot".
  4. As you move the selector, reach in and touch the A/C temperature valve actuator arm.
  5. Compare the movement to an operational vehicle, if possible.

Does the A/C temperature valve actuator arm make a complete travel?

--

Go to Step 2

Go to Step 3

2

Set the ignition switch to OFF. Refer to Temperature Valve Link Adjustment .

Does insufficient cooling and heating still exist?

--

Go to Heating Insufficient and Cooling Insufficient - Air Conditioning (A/C) Inoperative

System OK

3

  1. Set the ignition switch to OFF.
  2. Remove the temperature link rod from the temperature valve (snap out).
  3. Manually move the temperature valve to the right and to the left.

Does the temperature valve move right and left without sticking or binding?

--

Go to Step 4

Go to Step 5

4

  1. Set the ignition switch to OFF.
  2. Disconnect the HVAC control assembly connector C2.
  3. Set the ignition switch to RUN.
  4. Measure the voltage between HVAC control assembly connector C2 terminal H and ground. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 6

Go to Step 7

5

Replace the temperature valve.

Is the repair complete?

--

System OK

--

6

Measure the voltage between HVAC control assembly connector C2 terminal H and connector C1 terminal F. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 9

Go to Step 10

7

  1. Set the ignition switch to OFF.
  2. Inspect CKT 41 (BRN) for an open or short to ground.
  3. Inspect the instrument panel fuse block fuse 5D.

Did you find an open, short, or bad fuse?

--

Go to Step 8

--

8

Repair the open, short, or bad fuse. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

9

  1. Set the ignition switch to OFF.
  2. Inspect the HVAC control assembly connector C1 and connector C2 for proper terminal contact.

Is the terminal contact OK?

--

Go to Step 11

Go to Intermittents and Poor Connections

10

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1250 (BLK) for an open.
  3. If you find an open, repair the open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

11

  1. Reconnect the HVAC control assembly connector C1 and connector C2.
  2. Disconnect the A/C temperature valve actuator connector.
  3. Turn the ignition switch to RUN.
  4. Measure the voltage between A/C temperature valve actuator connector terminal 10 and ground. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 12

Go to Step 13

12

Measure the voltage between A/C temperature valve actuator connector terminal 10 and terminal 7. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage equal the specified value?

12 V

Go to Step 14

Go to Step 15

13

  1. Set the ignition switch to OFF.
  2. Inspect CKT 41 (BRN) for an open.
  3. If you find an open, repair the open.

Is the repair complete?

--

System OK

--

14

  1. Move the temperature selector from "Full Cool" to "Full Warm."
  2. As you move the selector, measure the voltage between A/C temperature valve actuator connector terminal 8 and terminal 7. Refer to Troubleshooting with a Digital Multimeter and Measuring Voltage in Wiring Systems.

Does the measured voltage vary within the specified range?

1 V (Full Cool) - 12 V (Full Warm)

Go to Step 16

Go to Step 17

15

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1791 (YEL) for an open or short to ground.
  3. Inspect the in-line connector C200 terminal K9 for proper terminal contact.
  4. If CKT 1791 and connector C200 are both OK, replace the heater and A/C control assembly. Refer to Control Assembly Replacement

Is the repair complete?

--

System OK

--

16

  1. Set the ignition switch to OFF.
  2. Inspect the A/C temperature valve actuator connector for proper terminal contact.
  3. If the connector is OK, replace the A/C temperature valve actuator. Refer to Temperature Actuator Replacement .

Is the repair complete?

--

System OK

--

17

  1. Set the ignition switch to OFF.
  2. Inspect CKT 1199 (DK BLU) for an open.
  3. Inspect the in-line connector C200 terminal K10 for proper terminal contact.
  4. If CKT 1199 and connector C200 are both OK, replace the heater and A/C control assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--