GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Interior Lights System Check performed?

--

Go to Step 2

Refer to Interior Lamps System Check

2

Check the underhood compartment lamp bulb. Is the bulb good?

--

Go to Step 4

Go to Step 3

3

Replace the underhood compartment lamp bulb.

Is the repair complete?

--

Refer to Interior Lamps System Check

--

4

Check the CTSY LP fuse 8 in the IP fuse block.

Is the fuse good?

--

Go to Step 5

Go to Step 6

5

  1. Turn ignition OFF
  2. Connect a Scan Tool
  3. Turn the ignition to the ON position
  4. Using the Scan Tool, check for DTCs in the Body Control Module (BCM)

Does the Scan Tool show any DTCs?

--

Refer to Diagnostic System Check - Body Control System in Body Control Systems

Go to Step 7

6

Locate and repair the short to ground in CKT 40 (ORN) and/or CKT 1732 (ORN) and replace the fuse.

Is the repair complete?

--

Refer to Interior Lamps System Check

--

7

Connect a test lamp from ground to terminal A4 of the body relay block.

Does the test lamp light?

--

Go to Step 9

Go to Step 8

8

Locate and repair open in CKT 40 from the body relay block terminal A4 to the IP fuse block terminal E5.

Is the repair complete?

--

Refer to Interior Lamps System Check

--

9

Disconnect BCM connector C1 and connect a fused jumper wire from ground to terminal A8 of the BCM C1 connector.

Does the underhood compartment lamp operate normally?

--

Go to Step 10

Go to Step 11

10

Replace the BCM.

Is the repair complete?

--

Refer to Interior Lamps System Check

--

11

Reconnect BCM connector C1 and connect a test lamp from ground to terminal C5 of the body relay block.

Does the test lamp light?

--

Go to Step 13

Go to Step 12

12

Replace the Inadvertant Power Relay.

Is the repair complete?

--

Refer to Interior Lamps System Check

--

13

Connect a test lamp from CKT 1732 (ORN) at the underhood lamp to ground.

Does the test lamp light?

--

Go to Step 15

Go to Step 14

14

Locate and repair the open in CKT 1732 (ORN) between underhood lamp and the body relay block.

Is the repair complete?

--

Refer to Interior Lamps System Check

--

15

With a DMM, check for continuity of the braided ground strap from the underhood compartment lamp housing base to the cowl stud.

Do you have continuity?

--

Go to Step 16

Go to Step 17

16

Replace the underhood compartment Lamp.

Is the repair complete?

--

Refer to Interior Lamps System Check

--

17

Locate and repair the open in the braided ground strap between the underhood lamp base and the cowl stud.

Is the repair complete?

--

Refer to Interior Lamps System Check

--