2 headlamp switches. 2 Ford part #s.....
E7SB-11654-AA
E7LB-11654-BA
1st is out of a 1987 Cougar
2nd is from a 1989 LSC.
Both had auto lamp and auto dim.
The switches APPEAR identical other than the part #....
1st one has a broken rheostat. It's from a friend's car. The plastic tab one of the contacts was mounted broke. Just want to make sure they are in fact compatible as I wanna give him the second if he can use it. It'll save him about $70....Maybe more.
Swapped it in. Working as it should. How hot do those heat sinks get? It's not ridiculously hot, but there's one spot about the size of a screw head warmer than the rest of it. I'll keep an eye on it.
It's the dimmer. It uses a resistive wire. If you leave the lights dim alot it will burn out the coiled wire. Also the whole current for the headlights run through the switch. A relay would do wonders there.
if you need verbal help with the slave relay mod , call me 304 772 3411,
the heat sync gets hot and does present a degree of voltage drop through the contacts.
the headlamps & marker lamps all add up to the heat on the switch.
i would need to compare my shop manual wring diagram to see if there is a difference from the Mark to Bird/coug but it seems your trial and error is working so far.
nice find on compatability.