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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Corvette 🢒 Body and Accessories 🢒 Data Link Communications 🢒 Air Delivery Improper

Air Delivery Improper CJ2

Air Delivery Improper <<CJ2>>

Step

Action

Value(s)

Yes

No

DEFINITION: Air flow is not being delivered from the proper mode outlet which was requested by the operator (CJ2).

1

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

--

Go to Step 2

Go to HVAC System Check

2
  1. Disconnect the vacuum line connector from the vacuum/electric solenoid.
  2. Connect a vacuum gauge to the purple vacuum line.
  3. Start the engine and allow it to idle in park.
  4. Measure the vacuum at the purple/black (engine source) vacuum line.

Is the vacuum reading within the specified values?

10-17 in.Hg

Go to Step 3

Go to Step 27

3
  1. Disconnect the vacuum gauge from the purple vacuum line connector.
  2. Connect a vacuum pump to each of the individual vacuum lines feeding each of the vacuum actuators at the vacuum/electric solenoid connector.
  3. Apply 15 to 20 inches of vacuum to each of the vacuum actuators through the corresponding vacuum line.
  4. When applying vacuum, listen for movement of the actuator door or vacuums leaks.

Do each of the vacuum actuators hold vacuum and apply the actuator door properly when vacuum is applied?

--

Go to Step 5

Go to Step 4

4
  1. Disconnect the inoperative vacuum actuator from the appropriate vacuum line connector.
  2. Connect a vacuum pump to the vacuum actuator.
  3. Apply 15 to 20 inches of vacuum to the vacuum actuator.
  4. When applying vacuum, listen for movement of the actuator door or vacuums leaks.

Does the vacuum actuator hold vacuum and apply the actuator door properly when vacuum is applied?

--

Go to Step 29

Go to Step 28

5
  1. Disconnect the vacuum/electric solenoid connector.
  2. Turn the ignition switch to the ON position.
  3. Connect a DMM between terminal 6 (CKT 41) of the vacuum/electric solenoid connector and a good ground.
  4. Measure the available voltage at the connector.

Is the voltage within the specified values?

10.0-14.0V

Go to Step 9

Go to Step 6

6

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

Is the fuse open?

--

Go to Step 7

Go to Step 8

7

Locate and repair a short to ground in CKT 41 between the instrument panel electrical center and the vacuum/electric solenoid connector.

Is the repair complete?

--

Go to HVAC System Check

--

8

Locate and repair an open or a high resistance in CKT 41 between the instrument panel electrical center and the vacuum/electric solenoid connector.

Is the repair complete?

--

Go to HVAC System Check

--

9
  1. Turn the ignition switch to the OFF position.
  2. Disconnect the HVAC Control Assembly.
  3. Vacuum/electric solenoid connector still disconnected.
  4. Connect a DMM between terminal 2 (CKT 1397) of the vacuum/electric solenoid connector and terminal D10 of the HVAC Control Assembly connector.
  5. Measure for continuity between these two terminals.

Is the resistance between these two connectors less than the specified value?

0.5ohms

Go to Step 10

Go to Step 11

10
  1. Vacuum/electric solenoid connector and the HVAC Control Assembly connector are still disconnected.
  2. Connect a DMM between the HVAC Control Assembly connector terminal D10 and ground.
  3. Measure for continuity to ground in CKT 1397.

Is CKT 1397 shorted to ground?

--

Go to Step 30

Go to Step 12

11

Locate and repair an open or high resistance in CKT 1397.

Is the repair complete?

--

Go to HVAC System Check

--

12
  1. Connect the DMM between terminal 1 (CKT 1395) of the vacuum/electric solenoid connector and terminal D11 of the HVAC Control Assembly connector.
  2. Measure for continuity between these two terminals.

Is the resistance between these two connectors less than the specified value?

0.5ohms

Go to Step 13

Go to Step 14

13
  1. Vacuum/electric solenoid connector and the HVAC Control Assembly connector are still disconnected.
  2. Connect a DMM between the HVAC Control Assembly connector terminal D11 and ground.
  3. Measure for continuity to ground in CKT 1395.

Is CKT 1395 shorted to ground?

--

Go to Step 31

Go to Step 15

14

Locate and repair an open or high resistance in CKT 1395.

Is the repair complete?

--

Go to HVAC System Check

--

15
  1. Connect the DMM between terminal 5 (CKT 1396) of the vacuum/electric solenoid connector and terminal D13 of the HVAC Control Assembly connector.
  2. Measure for continuity between these two terminals.

Is the resistance between these two connectors less than the specified value?

0.5ohms

Go to Step 16

Go to Step 17

16
  1. Vacuum/electric solenoid connector and the HVAC Control Assembly connector are still disconnected.
  2. Connect a DMM between the HVAC Control Assembly connector terminal D13 and ground.
  3. Measure for continuity to ground in CKT 1396.

Is CKT 1396 shorted to ground?

--

Go to Step 32

Go to Step 18

17

Locate and repair an open or high resistance in CKT 1396.

Is the repair complete?

--

Go to HVAC System Check

--

18
  1. Connect the DMM between terminal 3 (CKT 66) of the vacuum/electric solenoid connector and terminal D9 of the HVAC Control Assembly connector.
  2. Measure for continuity between these two terminals.

Is the resistance between these two connectors less than the specified value?

0.5ohms

Go to Step 19

Go to Step 20

19
  1. Vacuum/electric solenoid connector and the HVAC Control Assembly connector are still disconnected.
  2. Connect a DMM between the HVAC Control Assembly connector terminal D9 and ground.
  3. Measure for continuity to ground in CKT 66.

Is CKT 66 shorted to ground?

--

Go to Step 33

Go to Step 21

20

Locate and repair an open or high resistance in CKT 66.

Is the repair complete?

--

Go to HVAC System Check

--

21
  1. Connect the DMM between terminal 4 (CKT 1394) of the vacuum/electric solenoid connector and terminal D8 of the HVAC Control Assembly connector.
  2. Measure for continuity between these two terminals.

Is the resistance between these two connectors less than the specified value?

0.5ohms

Go to Step 22

Go to Step 23

22
  1. Vacuum/electric solenoid connector and the HVAC Control Assembly connector are still disconnected.
  2. Connect a DMM between the HVAC Control Assembly connector terminal D8 and ground.
  3. Measure for continuity to ground in CKT 1394.

Is CKT 1394 shorted to ground?

--

Go to Step 34

Go to Step 24

23

Locate and repair an open or high resistance in CKT 1394.

Is the repair complete?

--

Go to HVAC System Check

--

24
  1. Reconnect the vacuum/electric solenoid connector.
  2. Start the engine and allow it to idle.
  3. Momentarily connect a fused (15 A) jumper wire between ground and each of the following HVAC Control Assembly connector terminals: D8, D9, D10, D11 and D13.

When each terminal is grounded, does the corresponding vacuum/electric solenoid respond and allow the corresponding vacuum actuator to operate?

--

Go to Step 25

Go to Step 26

25

Replace the HVAC Control Assembly.

Refer to Control Assembly Replacement .

Is the repair complete?

--

Go to HVAC System Check

--

26

Replace the vacuum/electric solenoid.

Is the repair complete?

--

Go to HVAC System Check

--

27

Repair a leak or a pinch in the purple/black (engine source) vacuum line between the vacuum/electric solenoid connector and its vacuum source.

Is the repair complete?

--

Go to HVAC System Check

--

28
  1. Check for any poor connections.
  2. Check for any binding conditions.
  3. If OK, replace the inoperative vacuum actuator.

Refer to Temperature Actuator Replacement .

Is the repair complete?

--

Go to HVAC System Check

--

29

Repair a leak or a pinch in the vacuum line between the vacuum/electric solenoid connector and the inoperative vacuum actuator.

Is the repair complete?

--

Go to HVAC System Check

--

30

Locate and repair a short to ground in CKT 1397.

Is the repair complete?

--

Go to HVAC System Check

--

31

Locate and repair a short to ground in CKT 1395.

Is the repair complete?

--

Go to HVAC System Check

--

32

Locate and repair a short to ground in CKT 1396.

Is the repair complete?

--

Go to HVAC System Check

--

33

Locate and repair a short to ground in CKT 66.

Is the repair complete?

--

Go to HVAC System Check

--

34

Locate and repair a short to ground in CKT 1394.

Is the repair complete?

--

Go to HVAC System Check

--