Low beams not working, high beams work
#1
#4
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Yes the socket / connector are one in the same ( too used to calling things connectors ).
If the brights work, you will have voltage on only 1 of the 2 pins ( the 3rd is ground, which is black ).
The fuses, there are 2 fuses for the low beams ( cab fuse panel fuses 26 & 28 ) and 1 fuse for the high beams ( cab fuse 16 ).
Best to start with turning the headlamps on,and checking on the pin on the back of the fuse ( both sides ) for the low beams. Easier then yanking your headlamp housings out. Make sure you have a good ground when testing, as not to get a false reading.
If these are dead on both sides with the main headlamp switch turned to the head position, and the MFS in the low position, then there is a problem with the MFS, and time to remove and test it.
If the brights work, you will have voltage on only 1 of the 2 pins ( the 3rd is ground, which is black ).
The fuses, there are 2 fuses for the low beams ( cab fuse panel fuses 26 & 28 ) and 1 fuse for the high beams ( cab fuse 16 ).
Best to start with turning the headlamps on,and checking on the pin on the back of the fuse ( both sides ) for the low beams. Easier then yanking your headlamp housings out. Make sure you have a good ground when testing, as not to get a false reading.
If these are dead on both sides with the main headlamp switch turned to the head position, and the MFS in the low position, then there is a problem with the MFS, and time to remove and test it.
#5
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Sorry, threads on the MFS & cleaning it
https://www.f150online.com/forums/el...on-switch.html
https://www.f150online.com/forums/el...r-gremlin.html
The other you would see when taking it out, is a loose connector in the steering wheel column.
Which makes me think of another item, try moving the tilt on your steering wheel all the way down ( try low beams ) and all the way up ( try low beams again ).
This might diagnose the difference between the MFS and the connector.
https://www.f150online.com/forums/el...on-switch.html
https://www.f150online.com/forums/el...r-gremlin.html
The other you would see when taking it out, is a loose connector in the steering wheel column.
Which makes me think of another item, try moving the tilt on your steering wheel all the way down ( try low beams ) and all the way up ( try low beams again ).
This might diagnose the difference between the MFS and the connector.
#7
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#9
i have exactly the same problem, 1997 XLT - only high beams. I checked for power at both fuses and I have 12 V at each one - on opposite sides of the fuse - i.e. there is 12 V on the right hand socket on one, 12 V on the left hand on the other. Is that weird - or is that how the fuse box is wired in the back? Anyway, having power there would seem to rule out the switches - so what is left ( no autolamp in this truck)
#10
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i have exactly the same problem, 1997 XLT - only high beams. I checked for power at both fuses and I have 12 V at each one - on opposite sides of the fuse - i.e. there is 12 V on the right hand socket on one, 12 V on the left hand on the other. Is that weird - or is that how the fuse box is wired in the back? Anyway, having power there would seem to rule out the switches - so what is left ( no autolamp in this truck)
This is opposite sides of fuse 26 and 28 ?
You high beams, are they with the FTP feature ( flash to pass / pull back on the MFS ) or both FTP and normal operating ( push forward ) ?
If you have power to one side of fuses 26 & 28 with the main headlamp switch turned on, the MFS should be OK, as Fuses 26 & 28 are fed by the MFS.
If you test the back of the fuse for 26 & 28, and have power on both sides with the headlamp switch turned to the head position, time to check for power at the headlamp bulb connector.
PS : See you do not have Autolamps, do you have DRLs ?
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Pull the MFS and test it with the chart above, but if fuse slots #26 & #28 have no power with the main headlamp switch on, I would think MFS or the connector in the steering wheel column.
What relays did you swap, there are none without Autolamps on a 1997 ( see diagram above from the 1997 EVTM cell 85-1 headlamps, no autolamp )
What relays did you swap, there are none without Autolamps on a 1997 ( see diagram above from the 1997 EVTM cell 85-1 headlamps, no autolamp )
#14
Here is what I have so far:
Power on one side of both fuse sockets, fuses are good, no power at the light sockets. Is there a connector behind the fuse block that might have worked loose ( over a year ago I replaced the heater core, so all of the dash has been pulled out and stuck back in - in the process something might have been affected - again over a year ago).
Thanks for the help so far.
Power on one side of both fuse sockets, fuses are good, no power at the light sockets. Is there a connector behind the fuse block that might have worked loose ( over a year ago I replaced the heater core, so all of the dash has been pulled out and stuck back in - in the process something might have been affected - again over a year ago).
Thanks for the help so far.