GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the vehicle theft deterrent diagnostic system check?

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Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2

  1. Listen to and feel the THFT 1 relay in the underhood fuse block.
  2. Cycle the ignition from RUN to START several times.

Does the relay actuate?

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Go to Diagnostic System Check - Theft Deterrent

Go to Step 3

3

Has the theft deterrent module been replaced?

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Go to Step 5

Go to Step 4

4

Replace the theft deterrent module. Refer to Theft Deterrent Module Replacement . Refer to Programming Theft Deterrent System Components .

Have you completed the repair?

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Go to Diagnostic System Check - Theft Deterrent

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5

Replace the powertrain control module (PCM). Have you completed the repair?

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Go to Diagnostic System Check - Theft Deterrent

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