GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the entire headlight leveling system check performed?

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Go to Step 2

Go to Headlight Leveling System Check

2

  1. Disconnect the connector at the headlamp leveling switch.
  2. Place the ignition switch in the RUN position.
  3. Turn the headlamps on.
  4. Connect a test light between cavity 7 of the headlamp leveling switch connector on circuit 10 and ground.

Does the test light illuminate?

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Go to Step 4

Go to Step 3

3

Repair the poor connection or open in circuit 10.

Is the repair complete?

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Go to Step 11

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4

  1. Disconnect the connector at the headlamp leveling actuator.
  2. Connect a test light between cavity 3 of the headlamp leveling actuator connector on circuit 10 and ground.

Does the test light illuminate?

--

Go to Step 5

Go to Step 6

5

Connect a test light between the headlamp leveling switch connector cavity 6 for circuit 650 and connector cavity 7 for circuit 10.

Does the test light illuminate?

--

Go to Step 8

Go to Step 7

6

Repair the open in circuit 10 between S202 and S227.

Is the repair complete?

--

Go to Step 11

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7

Repair the poor connection or open in circuit 650.

Is the repair complete?

--

Go to Step 11

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8

  1. Reconnect the headlamp leveling switch.
  2. Connect a digital multimeter (DMM) to circuit 869 between cavity 3 of the headlamp leveling switch connector and ground.

Is voltage present?

--

Go to Step 9

Go to Step 10

9

Repair the open in circuit 869 between the headlamp leveling switch and S172.

Is the repair complete?

--

Go to Step 11

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10

Replace the headlamp leveling switch. Refer to Headlamp Leveling Switch Replacement

Is the repair complete?

--

Go to Step 11

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11

  1. Turn the ignition switch to the OFF position.
  2. Reconnect all connectors/components removed.

Have all repairs been made?

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Go to Headlight Leveling System Check

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