New guy needing some help
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New User
Joined: Feb 2016
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New guy needing some help
Hey all -
I recently just bought an 89 7.3 IDI with about 190k miles. The truck runs very well but I noticed once I got home that the clearance lights come on for a few minutes, then flicker and go out. I also noticed the horn is VERY weak - pretty much non existent. I went out this morning first thing and started it up and the lights worked for a few minutes then back out and the horn sounds stronger but I anticipate if I left the truck on for awhile longer it would be weak again.
I searched on this forum and others but couldn't find a solid answer as far as if these two things would likely be related, possibly sharing a harness or anything? It seems the rest of the electrical is just fine. The only other thing possibly electrical is the truck needed the key turned about 5 times when I left the dealer due to what I anticipate is a possible ignition issue, but may not be related.
Anyway - any tips would be helpful. I plan on troubleshooting it more but thought I'd pose the question in the meantime.
I recently just bought an 89 7.3 IDI with about 190k miles. The truck runs very well but I noticed once I got home that the clearance lights come on for a few minutes, then flicker and go out. I also noticed the horn is VERY weak - pretty much non existent. I went out this morning first thing and started it up and the lights worked for a few minutes then back out and the horn sounds stronger but I anticipate if I left the truck on for awhile longer it would be weak again.
I searched on this forum and others but couldn't find a solid answer as far as if these two things would likely be related, possibly sharing a harness or anything? It seems the rest of the electrical is just fine. The only other thing possibly electrical is the truck needed the key turned about 5 times when I left the dealer due to what I anticipate is a possible ignition issue, but may not be related.
Anyway - any tips would be helpful. I plan on troubleshooting it more but thought I'd pose the question in the meantime.
i ain't rite
Joined: Mar 2005
Posts: 65,422
Likes: 5,506
From: Marlboro Mental Hospital.
welcome to FTE.
the light issue sounds like a burned connector on the back of the headlight switch. common issue with these trucks if anyone added extra lights over the years.
as to the horns, they are 27 years old so they are probably just tired.
the horn are mounted under the driver side headlight and above the front bumper behind that little panel between the bumper and headlight.
the light issue sounds like a burned connector on the back of the headlight switch. common issue with these trucks if anyone added extra lights over the years.
as to the horns, they are 27 years old so they are probably just tired.
the horn are mounted under the driver side headlight and above the front bumper behind that little panel between the bumper and headlight.
Post Fiend
Joined: Nov 2005
Posts: 7,437
Likes: 4
From: Charles Town, W bygod Va
Adding headlight relays should eliminate that problem. I did a 4 relay system on both of my plow trucks. Ive been wanting to wire it up so all 4 headlights come on but been too lazy.
Thread Starter
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New User
Joined: Feb 2016
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welcome to FTE.
the light issue sounds like a burned connector on the back of the headlight switch. common issue with these trucks if anyone added extra lights over the years.
as to the horns, they are 27 years old so they are probably just tired.
the horn are mounted under the driver side headlight and above the front bumper behind that little panel between the bumper and headlight.
the light issue sounds like a burned connector on the back of the headlight switch. common issue with these trucks if anyone added extra lights over the years.
as to the horns, they are 27 years old so they are probably just tired.
the horn are mounted under the driver side headlight and above the front bumper behind that little panel between the bumper and headlight.
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i ain't rite
Joined: Mar 2005
Posts: 65,422
Likes: 5,506
From: Marlboro Mental Hospital.
for the ignition try putting a test light to the little lug on the fender starter relay while someone turns the key. if you get power to the wire and the engine does not turn over, the starter relay is bad. they are crap now that almost all are made in china, i have at times had to try 5-6 to get a good one new out of the box.
if you do not get power to the wire, it could be a separated ignition switch, or a cracked ignition actuator getting ready to break completely leaving you stranded.
when you turn the key to start, do you feel a slight spring resistance in the key and it returns to run position when you let go of it?
if you do not get power to the wire, it could be a separated ignition switch, or a cracked ignition actuator getting ready to break completely leaving you stranded.
when you turn the key to start, do you feel a slight spring resistance in the key and it returns to run position when you let go of it?
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New User
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for the ignition try putting a test light to the little lug on the fender starter relay while someone turns the key. if you get power to the wire and the engine does not turn over, the starter relay is bad. they are crap now that almost all are made in china, i have at times had to try 5-6 to get a good one new out of the box.
if you do not get power to the wire, it could be a separated ignition switch, or a cracked ignition actuator getting ready to break completely leaving you stranded.
when you turn the key to start, do you feel a slight spring resistance in the key and it returns to run position when you let go of it?
if you do not get power to the wire, it could be a separated ignition switch, or a cracked ignition actuator getting ready to break completely leaving you stranded.
when you turn the key to start, do you feel a slight spring resistance in the key and it returns to run position when you let go of it?
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New User
Joined: Feb 2016
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When I "accidentally" jumped it? I unplugged the wire that is connected to the smaller lug in between the battery lug and the ground lug. So, connecting the negative battery lug and the smaller one in between turned the alternator over.
i ain't rite
Joined: Mar 2005
Posts: 65,422
Likes: 5,506
From: Marlboro Mental Hospital.
ok. that really sounds like the relay is good. next step is to check the ignition switch.
if you remove the lower dash panels you will see 4 bolts holding the steering column up to the dash.
loosen them(do not remove them) and drop the column down a bit.
look in along the top of the column with a flashlight and you will see the ignition switch on top of the column in the area about above the brake pedal.
it is half plastic, half aluminum.
it should be one piece. if it looks like it is separated, this will cause your issue.
the switch is held to the top of the column with 2 bolts, if i remember correctly you need a 7/16 wrench to remove it. the ignition rod just sticks into the switch.
once down you can closely inspect the switch to see if it is solid or loose.
and once down you can also work the switch using a small screwdriver in the rod hole to see if the issue is in the switch or the actuator in the column.
if the truck starts every time by actuating the switch with a small screwdriver, then the problem is in the column and we can further direct you to get it working properly.
if you remove the lower dash panels you will see 4 bolts holding the steering column up to the dash.
loosen them(do not remove them) and drop the column down a bit.
look in along the top of the column with a flashlight and you will see the ignition switch on top of the column in the area about above the brake pedal.
it is half plastic, half aluminum.
it should be one piece. if it looks like it is separated, this will cause your issue.
the switch is held to the top of the column with 2 bolts, if i remember correctly you need a 7/16 wrench to remove it. the ignition rod just sticks into the switch.
once down you can closely inspect the switch to see if it is solid or loose.
and once down you can also work the switch using a small screwdriver in the rod hole to see if the issue is in the switch or the actuator in the column.
if the truck starts every time by actuating the switch with a small screwdriver, then the problem is in the column and we can further direct you to get it working properly.
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