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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Corvette 🢒 Body and Accessories 🢒 Data Link Communications 🢒 Blower Motor Medium Speed Inoperative

Blower Motor Medium Speed Inoperative Position 2

Blower Motor Medium Speed Inoperative (Position 2) <<C60>>

Step

Action

Value(s)

Yes

No

DEFINITION: Blower motor will operate at all speeds except medium speed (Position 2).

1

Were you sent here from the HVAC System Check (C60)?

--

Go to Step 2

Go to HVAC System Check

2
  1. Disconnect the HVAC Control Assembly connector C2.
  2. Disconnect the blower motor control module connector C1.
  3. Connect a fused jumper wire between terminal B and terminal G of the HVAC Control Assembly connector C2.
  4. Turn the ignition switch to the ON position.
  5. Connect the DMM between terminal A of the blower motor control module connector C1 and a good ground.
  6. Measure the available voltage at terminal A of the blower motor control module connector C1.

Is the voltage within the specified range?

10.0 -14.0V

Go to Step 4

Go to Step 3

3

Locate and repair an open or a high resistance in CKT 63.

Is the repair complete?

--

Go to HVAC System Check

--

4
  1. Remove the fused jumper wire.
  2. Connect the HVAC Control Assembly connector C2.
  3. Turn the blower switch to position 2.
  4. Turn the ignition switch to the ON position.
  5. Connect the DMM between terminal A of the blower motor control module connector C1 and ground.
  6. Measure the available voltage at terminal A of the blower motor control module connector C1.

Is the voltage within the specified range?

10.0 -14.0V

Go to Step 6

Go to Step 5

5

Replace the HVAC Control Assembly. Refer to Control Assembly Replacement .

Is the repair complete?

--

Go to HVAC System Check

--

6

Replace the blower motor control module. Refer to Blower Motor Resistor Replacement .

Is the repair complete?

--

Go to HVAC System Check

--

Blower Motor Medium Speed Inoperative Position 3

Blower Motor Medium Speed Inoperative (Position 3) <<C60>>

Step

Action

Value(s)

Yes

No

DEFINITION: Blower motor will operate at all speeds except medium speed (Position 3).

1

Were you sent here from the HVAC System Check (C60)?

--

Go to Step 2

Go to HVAC System Check

2
  1. Disconnect the HVAC Control Assembly connector C2.
  2. Disconnect the blower motor control module connector C1.
  3. Connect a fused jumper wire between terminal B and terminal F of the HVAC Control Assembly connector C2.
  4. Turn the ignition switch to the ON position.
  5. Connect the DMM between terminal D of the blower motor control module connector C1 and a known good ground.
  6. Measure the available voltage at terminal D of the blower motor control module connector C1.

Is the voltage reading within the specified range?

10.0 -14.0V

Go to Step 4

Go to Step 3

3

Locate and repair an open or a high resistance in CKT 72.

Is the repair complete?

--

Go to HVAC System Check

--

4
  1. Remove the fused jumper wire.
  2. Connect the HVAC Control Assembly connector C2.
  3. Turn the blower switch to position 3.
  4. Turn the ignition switch to the ON position.
  5. Connect the DMM between terminal D of the blower motor control module connector C1 and a known good ground.
  6. Measure the available voltage at terminal D of the blower motor control module connector C1.

Is the voltage reading within the specified range?

10.0 -14.0V

Go to Step 6

Go to Step 5

5

Replace the HVAC Control Assembly. Refer to Control Assembly Replacement .

Is the replacement complete?

--

Go to HVAC System Check

--

6

Replace the blower motor control module. Refer to Blower Motor Resistor Replacement .

Is the replacement complete?

--

Go to HVAC System Check

--

Blower Motor Medium Speed Inoperative Position 4

Blower Motor Medium Speed Inoperative (Position 4) <<C60>>

Step

Action

Value(s)

Yes

No

DEFINITION: Blower motor will operate at all speed except medium speed (Position 4).

1

Were you sent here from the HVAC System Check (C60)?

--

Go to Step 2

Go to HVAC System Check

2
  1. Disconnect the HVAC Control Assembly connector C2.
  2. Disconnect the blower motor control module connector C1.
  3. Connect a fused jumper wire between terminal B and terminal E of the HVAC Control Assembly connector C2.
  4. Turn the ignition switch to the ON position.
  5. Connect the DMM between terminal C of the blower motor control module connector C1 and a known good ground.
  6. Measure the available voltage at terminal C of the blower motor control module connector C1.

Is the voltage reading within the specified range?

10.0 -14.0V

Go to Step 4

Go to Step 3

3

Locate and repair an open or a high resistance in CKT 73.

Is the repair complete?

--

Go to HVAC System Check

--

4
  1. Remove the fused jumper wire.
  2. Connect the HVAC Control Assembly connector C2.
  3. Turn the blower switch to position 4.
  4. Turn the ignition switch to the ON position.
  5. Connect the DMM between terminal C of the blower motor control module connector C1 and a known good ground.
  6. Measure the available voltage at terminal C of the blower motor control module connector C1.

Is the voltage within the specified range?

10.0 -14.0V

Go to Step 6

Go to Step 5

5

Replace the HVAC Control Assembly. Refer to Control Assembly Replacement .

Is the replacement complete?

--

Go to HVAC System Check

--

6

Replace the blower motor control module. Refer to Blower Motor Resistor Replacement .

Is the replacement complete?

--

Go to HVAC System Check

--