I have a 77 f150 ranger xlt and the other day my dash lights started cutting in and out and that in turn made my headlights Dom each time the dash lights cut off and on. And I could hear a click coming from the light switch as well. So I replaced the switch and it worked for a lil bit but as soon as I hit a bump it started all over again. I've narrowed it down to the headlight switch connector but all the space connectors look fine. I tore apart my dash and had the switch just hanging while still connected and drive on a flat smooth surface. As soon as I kicked the switch, the dash lights started acting up. Any ideas?

 

The last time my headlight switch went out it melted a couple of the wires together a little ways down the harness. Have a good look.

 

Sounds like maybe a bad plug connector or a wear-worn spot/cut/mouse chew spot in the wiring somewhere.


Ck the harness for hot spots, melted wiring, that head light switch/wiring is NOT something to half ace, great way to burn your truck down.

 

it sounds like there is to much of a power draw on the switch lmc makes a kit for around 30 bucks that could possible solve the problem sevreral members have done this. its done through relay switches and pulls the juice strait from the battery

 

check your tail light harness i had a 73 f100 that done the same thing spent 3 days checking and re-wrapping all the harness just to find it was shorting where it comes through the bed

 

I've found the problem. There was a loom if writes ran under my battery tray and one of the mounts on the battery tray broke. So over time the battery tray had written two wires raw and was making them arc.

 

I have already put relays in on both the low and high beams. I've found the problem. There was a loom if writes ran under my battery tray and one of the mounts on the battery tray broke. So over time the battery tray had written two wires raw and was making them arc.