GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Horn Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Horns

2

  1. Disconnect the inoperative horn connector.
  2. Connect a test lamp between the horn connector CKT 29 (DK GRN) cavity B to ground.
  3. Press the horn button.

Does the test lamp illuminate for the left horn?

--

Go to Step 4

Go to Step 5

3

Repair the open in CKT 29 (DK GRN).

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 11

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4

Connect a test lamp between the left horn connector CKT 250 (BLK) cavity A to CKT 29 (DK GRN) cavity B.

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 8

5

Does the test lamp illuminate for the right horn?

--

Go to Step 6

Go to Step 3

6

Connect a test lamp between the right horn connector CKT 350 (BLK) cavity A to CKT 29 (DK GRN) cavity B.

Does the test lamp illuminate?

--

Go to Step 9

Go to Step 10

7

Replace the left horn. Refer to Horn Replacement .

Did you complete the replacement?

--

Go to Step 11

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8

Repair the open in CKT 250 (BLK).

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 11

--

9

Replace the right horn. Refer to Horn Replacement .

Did you complete the replacement?

--

Go to Step 11

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10

Repair the open in CKT 350 (BLK).

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 11

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11

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 2