GM Service Manual Online
For 1990-2009 cars only

Blower Motor Inoperative At Med-3 (Position 4) <<C60>>

Step

Action

Value(s)

Yes

No

DEFINITION: Blower motor will operate at all speed except Med-3 speed (Position 4).

1

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

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Go to Step 2

Go to HVAC Blower control System Check (C60)

2

  1. Disconnect the HVAC control head 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 head 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?

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Go to HVAC Blower control System Check (C60)

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4

  1. Remove the fused jumper wire.
  2. Connect the HVAC control head connector C2.
  3. Turn the blower switch to the Med-3 position.
  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 head.

Is the replacement complete?

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Go to HVAC Blower control System Check (C60)

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6

Replace the blower motor control module.

Is the replacement complete?

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Go to HVAC Blower control System Check (C60)

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