GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Heater Blower Controls System Check?

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Go to Step 2

Go to Heater Blower Controls System Check

2

  1. Place the ignition switch in the RUN position.
  2. Place the rear heater switch in the MEDIUM position.
  3. Use a test lampJ 35616-200 in order to backprobe from the rear heater resistor pack CKT 1925 (RED) cavity A to ground.

Did the test lamp light?

--

Go to Step 3

Go to Step 4

3

Inspect for a poor connection at the rear heater resistor pack.

Does a poor connection exist?

--

Go to Step 9

Go to Step 5

4

Use a test lampJ 35616-200 in order to backprobe from the rear heater switch CKT 1925 (RED) cavity B to ground.

Did the test lamp light?

--

Go to Step 6

Go to Step 7

5

Replace the rear heater resistor pack.

Refer to Auxiliary Blower Motor Resistor Replacement .

Is the repair complete?

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Go to Heater Blower Controls System Check

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6

Repair the open in CKT 1925 (RED) between the rear heater switch and the rear heater resistor pack.

Is the repair complete?

--

Go to Heater Blower Controls System Check

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7

Inspect for a poor connection at the rear heater switch.

Does a poor connection exist?

--

Go to Step 10

Go to Step 8

8

Replace the rear heater switch.

Refer to Control Switch Replacement - Auxiliary .

Is the repair complete?

--

Go to Heater Blower Controls System Check

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9

Repair the poor connection at the rear heater resistor pack.

Is the repair complete?

--

Go to Heater Blower Controls System Check

--

10

Repair the poor connection at the rear heater switch.

Is the repair complete?

--

Go to Heater Blower Controls System Check

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