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For 1990-2009 cars only

Air Temperature Control Inoperative CJ2

Air Temperature Control Inoperative <<CJ2>>

Step

Action

Value(s)

Yes

No

DEFINITION: Driver's side air temperature control is inoperative. No DTCs are set. The driver's side temperature control button is the master setting for both the LH and RH electric actuators. The following table will diagnose either of the following two conditions: (1) The driver's side temperature control button is adjusted and neither the LH or RH electric actuators respond accordingly. (2) The driver's side temperature control button is adjusted and only the RH electric actuator responds. LH actuator is inoperative.

1

Were you sent here from the HVAC System Check (CJ2)?

--

Go to Step 2

Go to HVAC System Check

2

  1. Disconnect the LH electric actuator connector.
  2. Turn the ignition switch to the ON position.
  3. Use a DMM to measure the voltage between terminal 5 of the LH electric actuator connector and ground.

Is the voltage within the specified range?

10.0-14.0V

Go to Step 4

Go to Step 3

3

Check the HVAC MiniFuse® #18 for an open circuit.

Is the fuse open?

--

Go to Step 17

Go to Step 18

4

  1. Connect the DMM between terminal 10 of the LH electric actuator connector and ground.
  2. Turn the ignition switch to the ON position.
  3. Measure the available voltage at terminal 10 of the LH electric actuator connector.

Is the voltage within the specified range?

4.0-6.0V

Go to Step 6

Go to Step 5

5

Locate and repair an open or a high resistance in CKT 1791 between the HVAC Control Assembly and the LH electric actuator connector.

Is the repair complete?

--

Go to HVAC System Check

--

6

Are both the LH and RH electric actuators inoperative when the driver's side temperature control is adjusted?

--

Go to Step 12

Go to Step 7

7

  1. Connect the DMM between terminal 9 of the LH electric actuator connector and ground.
  2. Turn the ignition switch to the ON position.
  3. Measure the available voltage at terminal 9 of the LH electric actuator connector.

Is the voltage within the specified range?

4.0-6.0V

Go to Step 10

Go to Step 8

8

  1. Backprobe the HVAC Control Assembly connector terminal C8 with the positive lead of the DMM.
  2. Connect the negative lead of the DMM to ground.
  3. Turn the ignition switch to the ON position.
  4. Measure the available voltage at terminal C8 of the HVAC Control Assembly connector when it is connected to the HVAC Control Assembly module.

Is the voltage within the specified range?

4.0-6.0V

Go to Step 9

Go to Step 15

9

Locate and repair an open or high resistance in CKT 733.

Is the repair complete?

--

Go to HVAC System Check

--

10

  1. Disconnect the HVAC Control Assembly connector.
  2. Connect a fused jumper between terminal 5 and terminal 6 of the LH electric actuator connector.
  3. Turn the ignition switch to the ON position.
  4. Use a DMM to measure the voltage between terminal C7 of the HVAC Control Assembly connector and ground.

Is the voltage within the specified range?

10.0-14.0V

Go to Step 12

Go to Step 11

11

Locate and repair an open or high resistance in CKT 1199.

Is the repair complete?

--

Go to HVAC System Check

--

12

  1. Turn the ignition switch to the OFF position.
  2. Connect the DMM between terminal D1 of the HVAC Control Assembly connector and terminal 7 of the LH electric actuator connector.
  3. Measure CKT 1798 for continuity between the HVAC Control Assembly connector and the LH electric actuator connector.

Is CKT 1798 continuous?

--

Go to Step 14

Go to Step 13

13

Locate and repair an open or a high resistance in CKT 1798.

Is the repair complete?

--

Go to HVAC System Check

--

14

  1. Reconnect all of the components back to their respective connectors.
  2. Connect the scan tool to the diagnostic link connector.
  3. Turn the ignition switch to the ON position.
  4. Select HVAC readout parameters on the scan tool.
  5. Rotate the LH side temperature control knob between full hot and full cold.
  6. Check for the LH MIX MTR POSITION REQUEST and the LH MIX MTR POSITION FEEDBACK signal on the scan tool.

Does the HVAC Control Assembly send a change in position request to the LH actuator but the LH actuator sends no feedback response to the HVAC control head?

--

Go to Step 16

Go to Step 15

15

Replace the HVAC Control Assembly.

Refer to Control Assembly Replacement .

Is the repair complete?

--

Go to HVAC System Check

--

16

  1. Check for any poor connections.
  2. Check for any binding conditions.
  3. If OK, replace the LH electric actuator.
  4. If through testing it was found that both electric actuators were inoperative, then replace both the LH and RH electric actuators.

Is the repair complete?

--

Go to HVAC System Check

--

17

Locate and repair a short to ground in CKT 41.

Is the repair complete?

--

Go to HVAC System Check

--

18

Locate and repair an open or a high resistance in CKT 41.

Is the repair complete?

--

Go to HVAC System Check

--