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HID's not working - Need Help Please
So here's the scenario....
Got in my truck the other night and both my HID's in my headlights would not come on...just the marker lights would come on. Checked all the fuses( L/R Low Beams) in the truck for headlights and they are all good. I checked all the fuses running from the battery to ballasts- fine. Checked the relays at the ballasts. Fine, although found out why one of the foglights wasn't working....bad relay. Checked the grounds - fine. It seems the ballasts aren't even getting power. I even disconnected part of the HID's so I could reconnect a OEM bulb and it doesn't even light. So my last thought is it may be a bad switch on the dash?...but that doesn't seem right as the marker lights still come on as well as the foglights. It would seem odd that both ballasts would go at the same time so I don't think that would be the issue at this time. I just don't know where else to check to see what may be the reason they aren't working. Any thoughts or ideas? |
If you checked the fuses for the low beams, and they have power on both sides ( "they are all good" ) it is not the MFS.
You did check the fuse with a meter on both sides with the main headlamp switched to on, not just look at them, right ? |
when I stuck the volt meter in the fuse panel while the headlamps are on I don't get any reading.
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How about some specifics to where you stuck the volt meter in the fuse panel.
This is a bit vague, and I don't want to make assumptions. In addition to the fuse panel, and Fuse #, please include if you did both sides of the fuse. Also are you using a test fuse to the same ground, to make sure the ground is good ? Right now I can guess either the MFS needs to be removed and tested or the ground is not a good ground. |
I tried 23(RH), 25(LH), and 40(Low Beam HL/DRL) at the fuse panel on the passenger side floor. swapping +/- of the volt meter in both sides of the fuse panel to test and did not get any readings. I did also try replacing with new fuses.
Both Grounds of the HID's are grounded right behind the headlight which is part of the frame. These grounds also share the grounds for the foglights (HID's) which still work fine. Sorry SCULLY, I don't know what you mean by MFS? |
I think it means "multi function switch" which is the turn signal lever.
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Originally Posted by Ronix
(Post 4167682)
I tried 23(RH), 25(LH), and 40(Low Beam HL/DRL) at the fuse panel on the passenger side floor. swapping +/- of the volt meter in both sides of the fuse panel to test and did not get any readings. I did also try replacing with new fuses.
Both Grounds of the HID's are grounded right behind the headlight which is part of the frame. These grounds also share the grounds for the foglights (HID's) which still work fine. Sorry SCULLY, I don't know what you mean by MFS? You have the reference ( black ) probe on 1 side of the fuse, and the reading probe ( red ) on the other side of the fuse. When you measure reference to itself, you should have 0 V ( else the 2 reference points have an issue ). You need to have ground ( lower right hand corner by the fuse panel is a ground lug ) on the black lead, and probe both sides of the fuse with the red lead. https://www.f150online.com/forums/me...e-check-01.jpg With the main headlamp switch turned to the head position, you should get + 12 V DC on both sides ( within 0.1 v DC ) same reading. Do this test for all 3 fuses you tested the other way. The ground check is for the meter, probe the power point or cigar lighter fuses ( hot all the time ) using the ground you are using the test the headlamp fuses, to make sure you get a reading if the headlamp fuses produce nothing. The MFS is MultiFunction Switch, as ELVATO posted. By testing the fuses this way, you know if you have to work back towards the MFS / main headlamp switch or towards the bulb connectors ( fuse is in between both of them ). How did you check the relays for the ballasts ? |
I checked the relays with a spare new relay that I had as an extra from when I ordered some replacements last time. They were faulty due to corrosion.
I will check the panel tonight and see what I can find. Appreciate all the help. |
When I had these exact same symptoms a few months back it ended up being the MFS.
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Originally Posted by Ronix
(Post 4167884)
I checked the relays with a spare new relay that I had as an extra from when I ordered some replacements last time. They were faulty due to corrosion.
...<snip>.... Might want to pull the relay, and jumper the normally open contacts as step #1 of testing the relay https://www.f150online.com/forums/me...auto-relay.jpg This will test the ballast, power to the ballasts and the HID lamps. The next step is to bench test the relay. Using the diagram above, apply power & ground to pins # 85 & #86. Connect a meter to pins # 30 & 87, with the function set as ohms ( resistance or continuity ). When you energize the coil ( pins 85 & 86 ), the ohms through the relay should be less than 200 ohms. |
Alright. I checked all three fuses. 40 has power. both 23 & 25 got nothing. So which way would that mean....between the switch on the dash and the panel?
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Originally Posted by Ronix
(Post 4168110)
Alright. I checked all three fuses. 40 has power. both 23 & 25 got nothing. So which way would that mean....between the switch on the dash and the panel?
If so, time to remove the MFS and test it. https://www.f150online.com/forums/me...s-headlamp.jpg |
Sorry SCULLY, I'm not quite sure what to do exactly here. I don't have a lot experience with Volt/Ohm meters.
on the meter I have black on common, red on ohms with the dial turned to 2K. If I read the above chart correctly ( some numbers are hard to read) I have red in 6 and black in 7. I get .095 If I move black to 8 and red to 9 I get .018 |
For what setting on the MFS ?
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All the way right to (low) headlamps.
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