GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Disconnect the auxiliary cooling fan relay.

Does the auxiliary cooling fan motor stop?

--

Go to Step 2

Go to Step 4

2

  1. Ensure that the ignition switch is in the Off position.
  2. Disconnect all the vehicle control module (VCM) connectors.
  3. Connect a test lamp between connector C4 terminal 9 and B+.

Does the test lamp light?

--

Go to Step 5

Go to Step 3

3

  1. Ensure that the recirculation button in the heater and A/C control module is out or in the Off position.
  2. Connect a test lamp between VCM connector C4 terminal 7 and B+.

Does the test lamp light?

--

Go to Step 6

Go to Step 7

4

Repair short to voltage in CKT 702 (RED) wire between auxiliary cooling fan relay and auxiliary cooling fan motor. Refer to Wiring Repairs .

Is the repair complete?

--

System OK

--

5

Repair short to ground in CKT 473 (DK BLU) wire between auxiliary cooling fan relay and VCM. Refer to Wiring Repairs .

Is the repair complete?

--

System OK

--

6

Repair short to ground in CKT 1614 (DK GRN) wire between the VCM and the heater and A/C control module. Refer to Wiring Repairs .

Is the repair complete?

--

System OK

--

7

Replace auxiliary cooling fan relay. Refer to Cooling Fan Relay Replacement - Auxiliary .

Is the repair complete?

--

System OK

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