GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check Performed?

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Go to Step  2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the ignition switch to the RUN position.
  2. Disconnect the Park/Neutral position switch connector C1.
  3. Connect a test lamp between the B terminal of connector C1 and ground.

Does the test lamp light?

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Go to Step  3

Go to Step  4

3

Connect a fused jumper between the B terminal and the F terminal of connector C1 of the Park/Neutral position switch.

Do the backup lamps light?

--

Go to Step  5

Go to Step  6

4

Backprobe the underhood junction block connector C1 with a test lamp between terminal F5 and ground.

Does the test lamp light?

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Go to Step  7

Go to Step  8

5

  1. Inspect the adjustment of the Park/Neutral position switch.
  2. If the adjustment is OK, replace the Park/Neutral position switch(LINK SWITCH R&R).

Is the repair complete?

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System OK

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6

  1. Reconnect the Park/Neutral position switch C1 connector.
  2. Place the transaxle in the REVERSE position.
  3. Backprobe the right IP junction block C2 connector with a test lamp between the B11 terminal and ground.

Does the test lamp light?

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Go to Step  9

Go to Step  10

7

Repair the open in CKT 539 between the underhood junction block and the Park/Neutral position switch. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

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8

Replace the underhood junction block. Refer to Underhood Fuse Block Replacement in Engine Electrical.

Is the repair complete?

--

System OK

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9

Backprobe the right IP junction block C3 connector between C2 terminal and ground or between B2 terminal and ground.

Does the test lamp light at both terminals?

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Go to Backup Lamp Inoperative - One Lamp

Go to Step  11

10

Repair the open in CKT 24 between the Park/Neutral position switch and the right IP junction block. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

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11

Replace the right IP junction block. Refer to Underhood Fuse Block Replacement in Engine Electrical.

Is the repair complete?

--

System OK

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