GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference: Brake Warning System Schematics

Connector End View Reference: Hydraulic Brake Connector End Views

1

Does the SERVICE ENGINE SOON indicator come on with the ignition switch in the RUN position?

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Go to Step 2

Go to Diagnostic System Check - Engine Controls in Engine Controls - 3.1L (LG8) or Diagnostic System Check - Engine Controls in Engine Controls - 3.8L

2

Inspect for a short to B+ on the signal circuit going to the IPC BRAKE indicator.

Is there a short to B+ on signal circuit?

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Go to Step 3

Go to Step 4

3

Repair the short to B+ on the signal circuit.

Has the repair been made and the system rechecked?

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System OK

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4

Inspect for a poor connection or an open in the signal circuit, between splice and the instrument cluster harness connector C2 terminal O.

Is there a poor connection or an open in signal circuit between splice and the instrument cluster harness connector C2 terminal O?

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Go to Step 5

Go to Step 6

5

Repair a poor connection or an open in the signal circuit between splice and the instrument cluster harness connector C2 terminal O.

Has the repair been made and the system rechecked?

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System OK

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6

  1. Inspect the warning indicator bulb and the bulb connection.
  2. If the bulb and the bulb connection are OK, replace the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console.

Has the repair been made and the system rechecked?

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System OK

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