GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

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

Refer to Instrument Panel, Gauges and Console

2

Check for a short to B+ on circuit 33.

Is there a short to B+ on circuit 33?

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Go to Step 3

Go to Step 4

3

Repair the short to B+ in circuit 33.

Has the repair been made and the system rechecked?

--

System OK

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4

Check for a poor connection or an open in circuit 33, between S207 and the instrument cluster harness connector C2 terminal O.

Is there a poor connection or an open in circuit 33 between S207 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 circuit 33 between S207 and the instrument cluster harness connector C2 terminal O.

Has the repair been made and the system rechecked?

--

System OK

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6

  1. Check the warning indicator bulb and bulb connection.
  2. If OK, replace the instrument cluster. Refer to Instrument Panel Cluster in Instrument Panel, Gauges and Console.
  3. Has the repair been made and the system rechecked?

--

System OK

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