GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Heater Blower Controls System Check performed?

--

Go to Step 2

Go to Heater Blower Controls System Check

2

  1. Remove the blower motor relay high.
  2. Connect a DMM between pin C1 and B2 of the relay.

Is there continuity?

--

Go to Step 4

Go to Step 3

3

Replace the blower motor relay high. Refer to Blower Motor Relay Replacement .

Is the repair complete?

--

Go to Heater Blower Controls System Check

--

4

  1. Disconnect the connectors at the blower motor.
  2. Connect a DMM between the blower motor connector C2, cavity B to ground.

Is there continuity?

--

Go to Step 5

Go to Step 8

5

Connect a DMM between the blower motor connector C1, cavity A and cavity C1 of the blower motor relay high.

Is there continuity?

--

Go to Step 6

Go to Step 9

6

  1. Reconnect the blower motor connectors.
  2. Connect a fused jumper wire between cavities A2 and C1 of the blower motor relay high, socket.

Does the motor spin freely?

--

Go to Step 10

Go to Step  7

7

Replace the blower motor. Refer to Blower Motor and Fan Replacement .

Is the repair complete?

--

Go to Heater Blower Controls System Check

--

8

Repair the open in CKT 150 (BLK) between the blower motor and ground G202. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Heater Blower Controls System Check

--

9

Repair the open in CKT 65 (PPL) between the blower motor relay high and the blower motor. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Heater Blower Controls System Check

--

10

  1. Disconnect the HVAC Control Module connector C2.
  2. Turn the ignition switch to the Run position.
  3. Connect a DMM between cavity G2 of the HVAC Control Module connector and ground.

Is battery voltage present?

--

Go to Step 12

Go to Step 11

11

Repair the open in CKT 141 (BRN) between the instrument panel (IP) fuse block and the HVAC control module. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Heater Blower Controls System Check

--

12

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

Is the repair complete?

--

Go to Heater Blower Controls System Check

--