Headlight problem. 97 F150
Headlight problem. 97 F150
I just got a fix-it ticket because of a problem with one of my headlights. The drivers side headlight is not as bright as the other one. I have DRLs and the light still isn't as bright as the other one. There are two filaments in the bulbs. One is for the DRL/low beam and the other is for the high beam. The problem is that the high beam for that light doesn't work either. Both bulbs were just replaced so one of them was about to go to begin with or the wiring harness is going bad. I am going to mess with it later on since I have other bulbs around. Does anybody else have any idea what could cause the problem? I'll post pictures later.
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Joined: Jun 2002
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From: Under the flightpath of old ORD 22R
If they are new bulbs, start with the obvious, pull the headlights out and swap the bulbs side for side, to see if the problem follows the bulb, or stays with the bulb connector.
If it stays with the connector, test the harness with a meter, to make sure :
1. a good ground connection.
1.1. Should read very low or zero ohms from the ground pin to the battery neg side. Black wire still on the '97 MY ( going from a 2005 EVTM at the moment ). Check with the voltage side of the meter first to be sure.
2. Check for correct voltage at the low beam side of the bulb connector
2.1. With a good ground now from step #1, test between the bulb ground and power. 2005 EVTM shows DG-OG for the wire color, might not be, again don't have access to the 97 EVTM at the moment.
3. Check voltage at the high beam side. the last wire not tested yet.
Without access to my 97 EVTM, I am taking a guess, but it should be close.
The low beams are fed directly via the MFS, with a fuse for each low beam, and the high beams are a single 20 AMP fuse ( did not find a high beam relay in the OM from fleetford ).
The other question is which side looks like it is not at full brightness ?
The fuse for the right headlamp, is also the same fuse for the DRL resistor.
Once you figure out if the bulb is the problem or not, and if you have a good circuit with ground and power, we can go from there. By that time I should be able to get to my '97 MY EVTM for a schematic, if another does not post it up, or have a direct answer.
If it stays with the connector, test the harness with a meter, to make sure :
1. a good ground connection.
1.1. Should read very low or zero ohms from the ground pin to the battery neg side. Black wire still on the '97 MY ( going from a 2005 EVTM at the moment ). Check with the voltage side of the meter first to be sure.
2. Check for correct voltage at the low beam side of the bulb connector
2.1. With a good ground now from step #1, test between the bulb ground and power. 2005 EVTM shows DG-OG for the wire color, might not be, again don't have access to the 97 EVTM at the moment.
3. Check voltage at the high beam side. the last wire not tested yet.
Without access to my 97 EVTM, I am taking a guess, but it should be close.
The low beams are fed directly via the MFS, with a fuse for each low beam, and the high beams are a single 20 AMP fuse ( did not find a high beam relay in the OM from fleetford ).
The other question is which side looks like it is not at full brightness ?
The fuse for the right headlamp, is also the same fuse for the DRL resistor.
Once you figure out if the bulb is the problem or not, and if you have a good circuit with ground and power, we can go from there. By that time I should be able to get to my '97 MY EVTM for a schematic, if another does not post it up, or have a direct answer.
Senior Member
Joined: Sep 1999
Posts: 3,083
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From: Ventura, California
I'm not sure if I'm understanding your problem correctly, but if you have one headlight that is dim, and the other might actually be brighter than normal, yet the bulbs are identical, the problem is almost certainly the ground wire for the brighter bulb has a bad connection. If this sounds like your problem, inspect the ground for the headlight that is brighter of the two, until you find the fault.
If I misunderstood you, remember this post next time you see your buddy in that situation, and tell him you know what's wrong.
Good luck!
Take care,
~Chris
If I misunderstood you, remember this post next time you see your buddy in that situation, and tell him you know what's wrong.
Good luck!
Take care,
~Chris
Technical Article Contributor
Joined: Jun 2002
Posts: 10,511
Likes: 10
From: Under the flightpath of old ORD 22R
Originally Posted by PKRWUD
...<snip>...If I misunderstood you, remember this post next time you see your buddy in that situation, and tell him you know what's wrong...<snip>..
Half the stuff we do in the states, as a normal course of driving, will get your license yanked in DE.
I remember the first time I went hauling on to the Autobahn outside Frankfurt on my way to Offenbeck, and I passed on the right outside lane ( what NA calls the slow lane )
They did not have a sense of humor about it at all.
Senior Member
Joined: Sep 1999
Posts: 3,083
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From: Ventura, California
Originally Posted by SSCULLY
That does not fly in DE. They are a bit more formal with driving rules then NA.
Half the stuff we do in the states, as a normal course of driving, will get your license yanked in DE.
I remember the first time I went hauling on to the Autobahn outside Frankfurt on my way to Offenbeck, and I passed on the right outside lane ( what NA calls the slow lane )
They did not have a sense of humor about it at all.
Half the stuff we do in the states, as a normal course of driving, will get your license yanked in DE.
I remember the first time I went hauling on to the Autobahn outside Frankfurt on my way to Offenbeck, and I passed on the right outside lane ( what NA calls the slow lane )
They did not have a sense of humor about it at all.
Right, he said he got a fix it ticket for this, so obviously the problem isn't cool with them, right?
BTW, Stuttgart was the very first place I ever saw McDonalds selling beer.
