no headlights..

While doing a check of lights, brake lights, hazard lights on my federal TC, I noticed I lost the main beam headlights when activating the floor mounted dimmer switch and the high beams did not turn on. Pushing the dimmer again, the main beams came back on. After this, I now have no headlights at all. The park/side light switch turns on the park light only. Am I correct in believing the sidelight circuit needs to be operational to activate the main beams and I need to find a park/sidelight switch? The wires to park/side light switch are in good shape and no fuses are blown. I have obtained a new Lucas 103sa dimmer and will install when I can find a wiring diagram to determine which wires go to which terminals.


Well-Known Member
Dont recall that headlights depend on sidelights working. All the fuses look OK? No distortion of the fuse block? Series 1 or 2 ? In a S2 I would bet on a fuse block problem....
Your floor switch and all the wiring connections are 50 years old and carry quite high current. Sounds like the culprit will be the floor switch which have their mounting holes either size of the button but the wires go in (plug) from the top (or bottom). Over time the rocking action of ones foot on the button can loosen the terminals and connectors so check those first and I'd solder the wires to the spade clips (if its old and dirty you might need to use plumbers flux to get it to stick). The floor switch wires are pretty thick and will hold their position when unplugged or you can run a loop of electrical tape around the bundle to stick them in place when removed.

From memory the Federal cars also have a 6RA relay for the lights next to the starter motor relay on the top of the inside guard and an earth point for both a little further up the guard which both need checking. You will also find there ar line connectors (bullet type) behind each headlight and side lights. There is normally enough wire stuffed in behind for you to pull the connects up high enough to work on. note these are not handed. the wires all end in bullets and are joined by a rubber cased tube. All three components need to be clean. They are available new for not much. I think martindale (USA) sell a very small Steel or brass pipe brush for cleaning the connectors.
Hi Mike. The car is a series 1 federal 2000 TC. Thanks for the info! Checked all connections, all wires look good, fuse box is in good shape. This car does not have a headlight relay. I finally had a chance to check power to/from the “park/sidelight” switch this morning. I have power to the switch, and power and function to parklight front and rear when park selected. When I select the sidelights, i have no power at the connection on the switch that sends power to sidelights, rt rear tail light and headlight switch.
So will order a replacement park/sidelight switch.
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