GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Express 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Headlamps Inoperative - One Lamp

Step

Action

Value(s)

Yes

No

1

Was the Headlight System Check performed?

--

Go to Step  2

Go to Headlight System Check

2

Are both low and high beam headlamps inoperative?

--

Go to Step 9

Go to Step 3

3

Is the left headlamp inoperative?

--

Go to Step 4

Go to Step 13

4

Is the low beam inoperative?

--

Go to Step 6

Go to Step 5

5

Is the high beam inoperative?

--

Go to Step 8

Go to Headlight System Check

6
  1. Connect an unpowered test lamp between the left headlamp connector cavity B for CKT 12 (TAN) and ground G108.
  2. Place the headlamp switch in the HDLP position.
  3. Place the headlamp dimmer switch in the LO position.

Does the test lamp light?

--

Go to Step 10

Go to Step 7

7

Locate and repair the open in CKT 12 (TAN) between the following components:

    • The underhood fuse relay center cavity G2
    • The left headlamp connector cavity B

Is the repair complete?

--

Go to Headlight System Check

--

8
  1. Connect an unpowered test lamp between the left headlamp connector cavity C for CKT 11 (GRN) and ground G108.
  2. Place the headlamp switch in the HDLP position.
  3. Place the dimmer switch in the HIGH position.

Does the test lamp light?

--

Go to Step 10

Go to Step 9

9

Locate and repair the open in CKT 11 (LT GRN) between the following components:

    • The underhood fuse relay center cavity G4
    • The left headlamp connector cavity C

Is the repair complete?

--

Go to Headlight System Check

--

10
  1. Disconnect the connector at the left headlamp.
  2. Connect a J 39200
    3. • The left headlamp connector cavity A for CKT 150 (BLK)
    • Ground G108

Is continuity present?

--

Go to Step 11

Go to Step 12

11

Replace the left headlamp assembly.

Is the repair complete?

--

Go to Headlight System Check

--

12

Locate and repair the open in CKT 150 (BLK) between the following components:

    • The left headlamp connector cavity A
    • Ground G108

Is the repair complete?

--

Go to Headlight System Check

--

13

Is the low beam inoperative?

--

Go to Step 15

Go to Step 14

14

Is the high beam inoperative?

--

Go to Step 17

Go to Headlight System Check

15
  1. Connect an unpowered test lamp between the right headlamp connector cavity B for the following components:
    2. • CKT 12 (TAN)
    • G109
  2. Place the headlamp switch in the HDLP position.
  3. Place the headlamp dimmer switch in the LO position.

Does the test lamp light?

--

Go to Step 19

Go to Step 16

16

Locate and repair the open in CKT 12 (TAN) between the following components:

    • The underhood fuse relay center cavity 12
    • The right headlamp connector cavity B

Is the repair complete?

--

Go to Headlight System Check

--

17
  1. Connect an unpowered test lamp between the following components:
    2. • The right headlamp connector cavity C for CKT 11 (LT GRN)
    • Ground G109
  2. Place the headlamp switch in the HDLP position.
  3. Place the headlamp dimmer switch in the HIGH BEAM position.

Does the test lamp light?

--

Go to Step 19

Go to Step 18

18

Locate and repair the open in CKT 11 (LT GRN) between the following components:

    • The underhood fuse relay center cavity J4
    • The right headlamp connector cavity C

Is the repair complete?

--

Go to Headlight System Check

--

19
  1. Disconnect the connector at the right headlamp.
  2. Connect a J 39200
    3. • The right headlamp connector cavity A for CKT 151 (BLK/WHT)
    • Ground G109

Is continuity present?

--

Go to Step 20

Go to Step 21

20

Replace the right headlamp assembly.

Is the repair complete?

--

Go to Headlight System Check

--

21

Locate and repair the open in CKT 151 (BLK/WHT) between the following components:

    • The right headlamp connector cavity A
    • Ground G109

Is the repair complete?

--

Go to Headlight System Check

--