GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Vivant 🢒 HVAC 🢒 HVAC - Automatic 🢒 Blower Motor Inoperative

Step

Action

Values

Yes

No

1
  1. Turn ON the ignition.
  2. Observe the temperature indication screen of the controller.

Does the digit flash?

--

Go to Step 2

Go to Step 3

2

Run a self-diagnosis circuit check.

Does the display indicate a defect code?

--

Go to appropriate DTC table

--

3

Inspect fuse F17 in the I/P fuse block and fuse EF4 in the engine fuse block.

Are fuses F17 and EF4 in good condition?

--

Go to Step 5

Go to Step 4

4

Repair any short circuit and replace the blown fuse.

Did you complete the repair?

--

System OK

--

5
  1. Turn ON the ignition.
  2. Measure the voltage between ground and terminal 87 of blower relay.

Does the voltage measure within the specified value?

11-14 V

Go to Step 13

Go to Step 6

6

Measure the voltage between ground and terminal 86 of the blower relay.

Does the voltage measure within the specified value?

11-14 V

Go to Step 8

Go to Step 7

7
  1. Turn OFF the ignition.
  2. Inspect the circuit between terminal 86 of the blower relay to F17 in the I/P fuse block.
  3. Repair any problem found in the wiring or terminals at the relay socket or connectors.

Did you complete the repair?

--

System OK

--

8
  1. Turn ON the ignition.
  2. Measure the voltage between the terminal 30 of the blower relay and ground.

Does the voltage measure within the specified value?

11-14 V

Go to Step 10

Go to Step 9

9

Repair the open circuit between terminal 30 of the blower relay and fuse EF4.

Did you complete the repair?

--

System OK

--

10
  1. Turn OFF the ignition.
  2. Using an ohmmeter, measure the resistance between terminal 85 of the blower relay and ground.

Does the resistance measure equal to the specified value?

0 ohms

Go to Step 12

Go to Step 11

11

Repair the open circuit between terminal 85 of the blower relay and ground.

Did you complete the repair?

--

System OK

--

12

Replace the blower relay.

Did you complete the repair?

--

System OK

--

13
  1. Turn OFF the ignition.
  2. Disconnect the blower motor connector.
  3. Turn ON the ignition.
  4. Measure the voltage between terminal 2 (YEL) and ground.

Does the voltage measure within the specified value?

11-14 V

Go to Step 15

Go to Step 14

14

Inspect the circuit from the blower relay to blower motor and repair as needed.

Did you complete the repair?

--

System OK

--

15

Measure the resistance between the connector terminals on the blower motor.

Does the resistance measure equal to the specified value?

0.5 ohms

Go to Step 17

Go to Step 16

16

Replace the blower motor.

Did you complete the repair?

--

System OK

--

17

Measure the resistance of the circuit between terminal 1 of the blower connector and terminal 30 of the blower high relay and terminal 6 of the power transistor.

Does the resistance measure equal to the specified value?

0 ohms

Go to Step 19

Go to Step 18

18

Repair the problem in the circuit.

Did you complete the repair?

--

System OK

--

19

Measure the resistance of the circuit from terminal 3 of the power transistor connector and terminal 87 of the high blower relay to ground.

Does the resistance measure equal to the specified value?

0 ohms

Go to Step 21

Go to Step 20

20
  1. Trace the circuit from terminal 3 of the power transistor connector and terminal 87 of the blower high relay to ground G203.
  2. Repair any problem found in the wiring, connector or ground.

Did you complete the repair?

--

System OK

--

21

Replace the power transistor.

Did you complete the repair?

--

System OK

Go to Step 22

22

Replace the FATC controller.

Did you complete the repair?

--

System OK

--