GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1998 🢒 Sonoma Pickup - 4WD 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Headlamps Inoperative - Right Low Beam

Step

Action

Value(s)

Yes

No

1

Did you perform the Headlight System Check?

--

Go to Step 2

Go to Headlight System Check

2

Use the scan tool in order to read the current body control module (BCM) diagnostic trouble codes (DTCs).

Is DTC B2575, B2577, B2600 set as a current code?

--

Go to Diagnostic System Check - Body Control System in Body Control System

Go to Step 3

3
  1. Disconnect the headlamp connector.
  2. Turn the headlamp switch to the HEAD position.
  3. Turn the multifunction switch to the LOW BEAM position.
  4. Connect a test lamp from the headlamp connector terminal A to ground.

Does the test lamp light?

--

Go to Step 5

Go to Step 4

4

Locate and repair an open in CKT 198 (DK BLU) between the following components:

    • The headlamp low beam bulb
    • The underhood bussed electrical center (UBEC)

Is the repair complete?

--

Go to Headlight System Check

--

5

Connect a test lamp from the headlamp connector terminal A to terminal B.

Does the test lamp light?

--

Go to Step 7

Go to Step 6

6

Locate and repair an open in CKT 525 (YEL) between the following components:

    • The headlamp
    • The UBEC

Is the repair complete?

--

Go to Headlight System Check

--

7

Replace the headlamp.

Is the repair complete?

--

Go to Headlight System Check

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