GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference: HVAC Schematics

DEFINITION: The right air temperature switch assembly will not adjust HVAC temperatures and no DTC's have been set.

1

Did you perform the HVAC Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Automatic

2

  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Auto HVAC with Dual Zone option parameter in the Dash Integration Module (DIM) Set Options data list.

Does the scan tool indicate that the Auto HVAC with Dual Zone option is active?

--

Go to Step 3

Go to Step 8

3

  1. Place the HVAC control module in AUTO mode.
  2. With a scan tool, observe the Pass. HVAC Switch parameter in the Driver Door Module data list.
  3. Press the warmer (red) switch and then the cooler (blue) switch on the right air temperature switch assembly.

Does the scan tool indicate that the Pass. HVAC Switch parameters are within the specified ranges?

Red: 127-158 Counts Blue: 51-81 Counts None: 204-234 Counts

Go to Step 4

Go to Step 15

4

  1. With a scan tool, observe the Right Program Number parameter in the Instrument Panel Integration Module data list.
  2. Press the warmer (red) switch and then the cooler (blue) switch on the passenger temperature control.

Does the Right Program Number parameter increase when the red switch is pressed and decrease when the blue switch is pressed?

--

Go to Step 5

Go to Step 17

5

Place the right air temperature switch in the coldest position

Do any of the red or blue indicators illuminate?

--

Go to Step 6

Go to Step 9

6

Place the right air temperature switch in the coldest position.

Did an indicator illuminate for each temperature adjustment except for neutral?

--

Go to Step 7

Go to Step 10

7

  1. Place the right air temperature switch assembly to the warmest position.
  2. Press OFF one time on the HVAC control module.

Did all of the right air temperature switch assembly indicators turn OFF?

--

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

Go to Step 17

8

With a scan tool, enable the Auto HVAC with Dual Zone option in the DIM Set Options data list.

Did you complete the repair?

--

Go to Step 21

--

9

  1. Turn OFF the ignition.
  2. Disconnect the right air temperature switch assembly. Refer to Air Temperature Switch Assembly Replacement - Right Side .
  3. Measure the voltage from the battery positive voltage circuit of the right air temperature switch assembly to a good ground.

Does the voltage measure near the specified value?

12 V

Go to Step 11

Go to Step 13

10

  1. Turn OFF the ignition.
  2. Disconnect the right air temperature switch assembly. Refer to Air Temperature Switch Assembly Replacement - Right Side .
  3. Disconnect the passenger door module. Refer to Door Control Module Replacement in Doors.
  4. Test the passenger door module passenger temperature signal circuits of the right air temperature switch assembly for a short to voltage, short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 21

Go to Step 12

11

Measure the voltage from the battery positive voltage circuit of the right air temperature switch assembly to the ground circuit of the right air temperature switch assembly.

Does the voltage measure near the specified value?

12 V

Go to Step 12

Go to Step 14

12

  1. Connect the passenger door module.
  2. Connect the right air temperature switch assembly.
  3. Turn ON the ignition, with the engine OFF.
  4. Place the HVAC control module in AUTO mode.
  5. Measure the voltage of the passenger door module passenger temperature signal circuits of the right air temperature switch assembly connected to a good ground.
  6. Place the right air temperature switch in the coldest position.

Does the voltage go to zero for at least one switch position for each circuit tested?

--

Go to Step 15

Go to Step 16

13

Test the battery positive voltage circuit of the right air temperature switch assembly for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 21

--

14

Test the ground circuit of the right air temperature switch assembly for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 21

--

15

Inspect for poor connections at the harness connectors of the right air temperature switch assembly and the passenger door module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 21

Go to Step 18

16

Inspect for poor connections at the harness connectors of the right air temperature switch assembly and the passenger door module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 21

Go to Step 19

17

Inspect for poor connections at the harness connector of the instrument panel integration module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 21

Go to Step 20

18

Replace the right air temperature switch assembly. Refer to Air Temperature Switch Assembly Replacement - Right Side .

Did you complete the replacement?

--

Go to Step 21

--

19

Replace the passenger door module. Refer to Door Control Module Replacement in Doors.

Did you complete the replacement?

--

Go to Step 21

--

20

Important:: Perform the recalibration procedure for the instrument panel integration module.

Replace the instrument panel integration module. Refer to Instrument Panel Module Replacement in Body Control System.

Did you complete the replacement?

--

Go to Step 21

--

21

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2