If the park-lamps are not coming on when you turn the headlights on (on your 1997-1998 F150, F250, or Expedition), then this is the tutorial you need to troubleshoot the problem.
All the test steps are explained in a step-by-step manner and are done with a multimeter.
Here are the contents of the tutorial at a quick glance:
- No Park-Lamps Troubleshooting Basics.
- TEST 1: Checking Fuse #7 Of The Power Distribution Center.
- TEST 2: Making Sure The Headlight Switch Is Getting Power.
- TEST 3: Jumpering The Park-Lamps Circuit.
- TEST 4: Testing The Continuity Of The Park-Lamps Circuit.
- Where To Buy The Headlight Switch And Save.
- More Ford 4.6L, 4.8L Tutorials.
NOTE: If you need to test the head-lamp circuit of the headlight switch, see this tutorial: Testing A No Low-Beam Headlights Problem (1997-1998 Ford F150).
The following tutorial may also be of interest:
No Park-Lamps Troubleshooting Basics
In a nutshell, this is what happens when you turn the headlight switch to the ‘Park-Lamps On’ or ‘Headlights On’ position:
- The headlight switch has power available at all times for the park-lamps on the tan with white stripe (TAN/WHT) of the grey 7-terminal connector.
- When you turn the headlight switch to the ‘park-lamps on’ or the ‘head-lamps on’ position, the switch now channels battery power (from the TAN/WHT wire) to the brown (BRN) wire of the grey 7-terminal connector.
- The BRN wire now feeds this battery power to all of the park-lamps in the front and rear of your F150 (F250, or Expedition).
The headlight switch, on the 1997-1998 F150 (F250, and Expedition) has three connectors. The one that we're gonna' worry about, to test the park-lamps, is the 7-terminal grey connector.
In the table below you'll find a brief description of the two terminals we need to test in this tutorial:
|Grey 7-Terminal Headlight Switch Connector|
|4||Brown (BRN)||Battery (+) Out (Park-Lamps)|
|5||Tan w/ White stripe (TAN/WHT)||Battery (+) In (Park-Lamps)|
Let's get started with the first test...
TEST 1: Checking Fuse #7 Of The Power Distribution Center
The first thing we're gonna' do is check that fuse #7 (15 A) of the Power Distribution Center (under-hood fuse/relay fuse box) is not blown.
Fuse #7 is the fuse that feeds power to the park-lamps circuit of the headlight switch.
If the fuse is OK, then we need to make sure that there's power at the TAN/WHT wire of the headlight switch's grey connector (in TEST 2).
OK, let's get started:
Locate and check fuse #7 (15 A) of the underhood fuse box.
Fuse #7 feeds battery power to the park lamps circuit of the headlight switch.
Remove the fuse and visually inspect it. The fuse should not be blown.
Let's interpret your test results:
CASE 1: Fuse #7 is OK. So far so good, since this is the correct and expected test result.
Your next step is to go to: TEST 2: Making Sure The Headlight Switch Is Getting Power.
CASE 2: Fuse #7 is blown. 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.