Headlight, Running light issue

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Aug 27, 2020 | 11:46 AM

#16

7.3_4Life

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From: Tennessee

No, They only come on when I pull the switch a little more out past 1/2 way

Aug 27, 2020 | 12:16 PM

#17

Perk85F250

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Quote:

Originally Posted by 7.3_4Life

No, They only come on when I pull the switch a little more out past 1/2 way

I suspect there is a bad connection on the fuse #4 circuit (tan/white) as mentioned earlier by Lone Wolf. Inspect the terminals in the fuse box for loose contact or corrosion. Wires on the back side of the fuse box can break, but it is rare. Click on the link for testing the light circuits and switch. The headlight circuit for your truck is basically the same.
https://troubleshootmyvehicle.com/fo...light-switch-1

Aug 27, 2020 | 12:28 PM

#18

lonewolf_

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Quote:

Originally Posted by 7.3_4Life

No, They only come on when I pull the switch a little more out past 1/2 way

How is that Possible IF you have no power on Terminal 'A' Tan/wht wire... .... if this is the case and you are getting park lights then either you have the wrong Headlight switch or the pigtail you wired in is not wired in correctly see the schematic I posted.

do a Continuity test on the switch to be sure it matches the functions of the Schematic ...Find out why you do not have power on the Tan/Wht wire ... it seems that you said you have power on Fuse #4 so is the wire burned open ???

IF you do not understand the schematic we can help with that too.

Aug 27, 2020 | 12:53 PM

#19

lonewolf_

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OK from the schematic you can call pin 'B' "B1" and call 'A' "B2" ... then you can use this guide https://troubleshootmyvehicle.com/fo...light-switch-1

Aug 27, 2020 | 02:17 PM

#20

7.3_4Life

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From: Tennessee

The headlight circuit works, the parking light circuit does not.

Aug 27, 2020 | 03:06 PM

#21

Perk85F250

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Quote:

Originally Posted by 7.3_4Life

The headlight circuit works, the parking light circuit does not.

Click on the link posted earlier, see page 3 for the park lights.

Aug 27, 2020 | 03:16 PM

#22

7.3_4Life

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From: Tennessee

In my case B2 (Tan/Wht Wire) has no power. and its the same wire that runs to the fuse, right? The fuse has power, so im lost.

Aug 27, 2020 | 03:22 PM

#23

lonewolf_

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Quote:

Originally Posted by Perk85F250

I guess I missed your comment

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Aug 27, 2020 | 03:24 PM

#24

7.3_4Life

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From: Tennessee

The wire that runs from the fuse (Tan/Wht) runs behind a metal piece that holds the dash in place and I can get behind that to see where it goes.

Aug 27, 2020 | 03:26 PM

#25

lonewolf_

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Quote:

Originally Posted by 7.3_4Life

In my case B2 (Tan/Wht Wire) has no power. and its the same wire that runs to the fuse, right? The fuse has power, so im lost.

right that wire runs from the fuse.

it should be hot at all times, IF not then the Park Lights will never come on.

IF fuse #4 has power on both sides of the Fuse then trace that wire to see where it is OPEN.

As mentioned it could be on the back of the fuse box where it connects to the fuse. or it could be a bad Splice.

Aug 27, 2020 | 05:07 PM

#26

Perk85F250

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Quote:

Originally Posted by 7.3_4Life

The wire that runs from the fuse (Tan/Wht) runs behind a metal piece that holds the dash in place and I can get behind that to see where it goes.

You are on the right track. I strongly recommend going through the diagnostic steps using the trouble shoot website link.

If you find the fuse box or wiring to it is the problem, it may be more practical to bypass the fuse box. Install an inline fuse and additional length of wire from Batt+ to the tan/white wire near the headlight switch. Batt+>inline fuse>headlight switch.

I had to do a similar bypass for the blower motor circuit in my truck. The amp draw from the motor caused the fuse and terminals to melt. New inline fuse and blower motor fixed it.

Aug 27, 2020 | 06:58 PM

#27

lonewolf_

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IF you have to add a new wire the easiest thing to do is just place a 15 AMP fuse between the Blk/Orn wire and the Tan/Wht wire, you can do this when splicing in the pigtail

See the Schematic I posted it will be between pin 'B' and 'A'

Sep 16, 2020 | 02:04 PM

#28

7.3_4Life

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From: Tennessee

Little late now, today I ran a wire from the battery to the tan/white wire on the switch with an inline fuse, and everything worked when I pulled the switch out.

Sep 16, 2020 | 02:17 PM

#29

DarkOverCast

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Quote:

Originally Posted by 7.3_4Life

Little late now, today I ran a wire from the battery to the tan/white wire on the switch with an inline fuse, and everything worked when I pulled the switch out.

I had to do something similar for my running light power. So far no issues

Sep 16, 2020 | 03:15 PM

#30

Perk85F250

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Quote:

Originally Posted by 7.3_4Life

Little late now, today I ran a wire from the battery to the tan/white wire on the switch with an inline fuse, and everything worked when I pulled the switch out.

Good to hear you got it fixed