Testing A No Low-Beam Headlights Problem (1997-1998 Ford F150)

TEST 2: Checking Fuses #16, #26, And #28 Of The Dash Panel Fuse Box

Checking Fuses #16, #26, And #28 Of The Dash Panel Fuse Box. How To Test A No Low-Beams Headlight Problem (1997, 1998 F150, F250, And Expedition)

We're now gonna' check the condition of fuses #16, #26, and #28 of the fuse/relay box located inside your Ford pick-up.

Fuse #16 protects the hi-beam circuit for both the right and left head-lamps. Fuse #26 protects the right-side low-beam circuit (between the headlight switch and the right head-lamp). Fuse #28 protects the left-side low-beam circuit (between the headlight switch and the left head-lamp).

OK, let's get started:

  1. 1

    Locate fuse #16 (20 A), fuse #26 (10 A), and fuse #28 (20 A) of the under dash fuse box.

  2. 2

    Check fuse #16 (20 A), fuse #26 (10 A), and fuse #28 (20 A) to see if they are blown.

Let's interpret your test results:

CASE 1: All fuses are OK. So far so good, since this is the correct and expected test result.

The next step is to make sure that there's power at the headlight switch connector. Your next step is to go to: TEST 3: Making Sure The Headlight Switch Is Getting Power.

CASE 2: Found a blown fuse. Replace the fuse and retest.

If the fuse gets blown again when you turn on the head light switch, then your next step should be remove the headlight switch and test the continuity of the power circuit for shorts to Ground between the fuse-box and the headlight switch connector.

TEST 3: Making Sure The Headlight Switch Is Getting Power

Making Sure The Headlight Switch Is Getting Power. How To Test A No Low-Beams Headlight Problem (1997, 1998 F150, F250, And Expedition)

So far, you've checked the fuses in the under-hood fuse-relay box and the dash panel fuse/relay box. Now, we're gonna' make sure that power is present at terminal #4 of the black headlight switch connector.

The wire that feeds battery power to female terminal #4 (of the black connector) is the dark blue with orange stripe (DK BLU/ORG) wire.

NOTE: All of the test steps in this tutorial assume that you have removed the headlight switch from its place on the instrument panel.

OK, this is what you need to do:

  1. 1

    Place your multimeter in Volts DC mode

  2. 2

    Check that terminal #4, of the black connector, has 10 to 12 Volts DC.

    The wire that feeds battery power to terminal #4 is the DK BLU/ORG wire.

  3. 3

    Battery power should be present with the key on or the key off.

Let's interpret your test results:

CASE 1: 10 to 12 Volts are present. So far so good, since this is the correct and expected test result.

Your next step is to go to: TEST 4: Jumpering The Headlight Circuit.

CASE 2: Battery power IS NOT present. This usually means that fuse #8, of the engine compartment fuse box, is blown. But you have already checked the fuse (in TEST 1). So this usually means that there's an open-circuit problem in this circuit.

Although it's beyond the scope of this tutorial to test this problem, your next step is to get a wiring diagram and test the continuity of this power circuit between the connector and the fuse box and repair the open-circuit.

Ford Vehicles:

  • Expedition
    • 1997, 1998
  • F150
    • 1997, 1998
  • F250
    • 1997, 1998