GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference: HVAC Schematics

Connector End View Reference: Component Connector End Views

1

Inspect other instrumentation lights.

Are other lights OFF?

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Go to Diagnostic System Check - Vehicle to diagnose lighting first.

Go to Step 2

2

  1. Remove the controller.
  2. Measure the voltage between terminals A3 and A4 of the controller connector.

Does the voltage measure within the specified range?

11-14 V

Go to Step 4

Go to Step 3

3

Repair the wiring harness between splice S204 and controller connector terminal A4 or between splice S203 and controller connector terminal A3

Did you complete the repair?

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System OK

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4

Inspect the illumination lamps.

Is 1 lamp burned out?

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Go to Step 5

System OK

5

Replace the burned out illumination lamp.

Did you complete the replacement?

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System OK

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