Headlight electrical gremlins???
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From: Americas' hat (Canada)
Headlight electrical gremlins???
Recently, on my dads' 02 F-350 dually, the low beams went out. Not one after the other, both at the same time. And it happened while he was backing into our driveway.
I went out and took a look at it, and noticed that the foglights weren't working either.
I looked at all the fuses, and they are all fine. Highbeams and Flash to Pass work, and i think the DRL's still work too.
I did a quick check on the switch (simply turning it to all positions) and it does work correctly as far as I know of. So where else should I be looking?
I do still need to replace a bulb to see if it is a bulb issue, but if it isn't what should I be looking for?
I went out and took a look at it, and noticed that the foglights weren't working either.
I looked at all the fuses, and they are all fine. Highbeams and Flash to Pass work, and i think the DRL's still work too.
I did a quick check on the switch (simply turning it to all positions) and it does work correctly as far as I know of. So where else should I be looking?
I do still need to replace a bulb to see if it is a bulb issue, but if it isn't what should I be looking for?
Elder User
Joined: Jun 2008
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From: Iowa
the multifunction switch in the column is the dimmer switch as well. Start checking there. Those do wierd stuff when they go bad. My bet is that the power is not getting through the dimmer contacts correctly.
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From: SE Wisco
Did you replace the fuse or just take it out and stare at it? I know when my #30 blew it looked good but was bad. You should at least get the DMM out and check continuity.
Jim et al - Do you think that thing is what makes my low beams come on with the park lights and stay on with the high beams? I can't complain bc it is a free Bright Box, but I suppose I shoud fix it someday.
Jim et al - Do you think that thing is what makes my low beams come on with the park lights and stay on with the high beams? I can't complain bc it is a free Bright Box, but I suppose I shoud fix it someday.
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Hotshot
Joined: Jan 2008
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From: Rochdale MA
Did you replace the fuse or just take it out and stare at it? I know when my #30 blew it looked good but was bad. You should at least get the DMM out and check continuity.
Jim et al - Do you think that thing is what makes my low beams come on with the park lights and stay on with the high beams? I can't complain bc it is a free Bright Box, but I suppose I shoud fix it someday.
Jim et al - Do you think that thing is what makes my low beams come on with the park lights and stay on with the high beams? I can't complain bc it is a free Bright Box, but I suppose I shoud fix it someday.
John, I emailed you the diagrams.
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From: Americas' hat (Canada)
We have replaced fuses, which did not fix the issue.
We replaced the bulbs, which did not fix the issue.
We replaced the multifunction switch which did not fix the issue.
After looking at the wiring diagram, our only thought is that the DRL relay might be the culprit.
So, how does one go about checking this relay without buying a new one first?
We replaced the bulbs, which did not fix the issue.
We replaced the multifunction switch which did not fix the issue.
After looking at the wiring diagram, our only thought is that the DRL relay might be the culprit.
So, how does one go about checking this relay without buying a new one first?
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From: SE Wisco
Did you buy the new headlight switch or the new multifunciton switch or both by now? The only reason I ask is bc IIUC they are two different things and I only saw you mention the headlight switch until now. (Which I assume you mean on off **** to the left of the steering wheel)
Hotshot
Joined: Jan 2008
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From: Rochdale MA
Relays are a little tricky to bench test unless you have a base and sometype of external power supply. if it matches up with any of the other relays then you can swap it out to see if it fixes the problem.
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From: Americas' hat (Canada)
sflem849 I actually just realized a few minutes ago that I was using the wrong terminology.
We replaced the main headlight switch, not the multifunction switch.
So how can I go about testing the multifunction switch to see if that is the issue.
Also, where can I find the daytime running light relays?
We replaced the main headlight switch, not the multifunction switch.
So how can I go about testing the multifunction switch to see if that is the issue.
Also, where can I find the daytime running light relays?
Laughing Gas
Joined: Aug 2008
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From: Dallas, Oregon
At least on the '01 they are behind the glove box. It looks like there are two. One should have five terminals in use (#1 relay) and the other four terminals is use (#2 relay). If the relays look the same, look at the sockets and count the number in use. The #1 relay with the five terminals is the one you likely are looking for. If it is a standard square relay, then with the low beams on, there should be 12 volts at the center terminal (87a). If there is not 12 volts there, then you need to look at the multifunction (turn signal) switch at the steering column. If you have power at the second (inboard) terminal, but not at the end terminal, you have a bad switch.
On the '01, there should be 12 volts at the RD/YE (red with yellow tracer) wire coming out of the multifunction switch on one end of the plastic connector. This connector has five terminals and has squared-off corners. There should also be 12 volts going into the multifunction switch at the RD/YE wire next to the one you just tested, but closer to the center of the connector.
On the '01, there should be 12 volts at the RD/YE (red with yellow tracer) wire coming out of the multifunction switch on one end of the plastic connector. This connector has five terminals and has squared-off corners. There should also be 12 volts going into the multifunction switch at the RD/YE wire next to the one you just tested, but closer to the center of the connector.
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From: Americas' hat (Canada)
I don't see what looks like relays behind the glove box. I only see a black box with 2 connections going in, and the blower motor.
One of the connections to the black box has 4 wires going in, one of which is RD/YE. The other connection has about 6 or 7 wires though.
So I'm not positive if this is what I'm looking for.
Could you possibly post a picture of it?
One of the connections to the black box has 4 wires going in, one of which is RD/YE. The other connection has about 6 or 7 wires though.
So I'm not positive if this is what I'm looking for.
Could you possibly post a picture of it?
Elder User
Joined: Jun 2008
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From: Iowa
what you might try is jumpering around the multifunction switch...diconnect switch, with the open face connector...... find a pinout of the connector, find the wire that goes to the headlights thats supposed to be hot going out, jump 12vdc live power to it and see if the lights come on. Or buy a new switch and trade it.