failed light switch

Or just use an in-line blade fuse holder

Radio Shack sells them, they have a cover that snaps over the top of the fuse and keeps it protected.
 
Pre Bertone 1500 light switch variants...

...pin locations ARE different between the switch with "lights" word
vs the switch with light beam icon.
Not plug n' play, but functionally the same,
so wire swapping should allow it to work.

BTW, kudos on your fix of old switch.
I had similar issue with my Strada headlight switch,
but cannibalized a spare X switch for the spring loaded dealy inside.
 
Went to leave work, turned on lights, lately the issue was I could have headlights or running lights but not both, I'm sure it's the switch, I mess with it, get headlights up and on and then try for running lights, can't seem to convince it, then the switch (which I'm holding in my hand) feels REAL warm, I shut the lights down and drive home in stealth mode (it was twilight, I barely "made it").
Took switch apart, same failure, super heat at the contact enough that when I went to pull the connector off the back of the switch, the spade stayed in!. This switch is now officially "baked" (pun intended).
I'm wondering if the switch was shorting internally causing all the heat and destruction or something else isn't correct and the switch is just the weak link that gives.
I'll head out to check which terminal it was, the letter melted off the back. Seems like this terminal is the one that would be initiated in "all on" mode. Interesting. A bit scary but interesting.
Baked Switch

There's a brown jumper between terminal V (also has a black coming off it, it's a dual) and the fried terminal (letter melted away) this wire shows heat damage. Blue/Red from terminal I is also fried. Have to go see if I can figure out where blue/red goes (parking lights?) I think the lower bank I, D and ? (melted) are for parking lights and also trigger headlight motors. This is the fried circuit and hopefully just due to switch failure. Hoping to get new (but wrong year) switch hooked up without connector, just put my own female spades on wires from harness and plug into correct male spades from switch.
 
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Makes me wonder...

Is there a larger than stock load on it? Not that it was really up to a stock load anyway. :sigh:

I'd check for loose connections in all the lighting circuits. Any loose or corroded connection will increase the load, and could cause your issues. As could any kind of aftermarket lighting, as well as just plain old halogen headlights. Today's sealed halogens are higher wattage than what the car was designed for.

You may also want to look at all the bulbs in your lighting and make sure you've got the proper wattage bulbs in the system.
 
Okay, I should add that I am now running relays on the headlights, not on the parking lights though.......maybe I should be. I still wonder if the switch shorted causing it to heat melt and make it worse, or, if as you say, the load was too great, causing it to go, then why the load and why with headlights on relays, there shouldn't be much load unless something in the parking light circuit is FUBAR'd.....

I haven't yet figured out where which wire heads, wiring diagram I have is just too complicated for little 'ol me. Looks like Lt.Blue/Red goes to "lighting relay". Interesting the diagram doesn't show the dual black brown (this brown is a jumper between the black and the burned terminal).
Going by:
http://www.midwesternmedicalmachine.com/~damonfg/x_wiring/81/02 Page 02 Headlights.jpg
 
It may be just the switch....

....if a connection/contact has deteriorated, the excessive resistance in the circuit will cause overheating of the already poor contact & cause meltdown, etc... of the switch or area surrounding the poor contact.

Since you know the switch is bad, replace that first before worrying about the rest of the circuitry.

Just cut & replace any terminal ends that show evidence of overheating.
 
It's probably just the switch, but check for proper fuses

If you had to mess with the switch to get it to do what it's supposed to do then it was likely already messed up internally.

The only load that should be going through the switch now is the parking lights. My first relay mod also did the parking lights, but that is only because another mod I did raised the parking light current on the orignal car. It shouldn't be needed on a stock parking light setup.

BEFORE you install the new switch, verify that the fuse ratings are correct for the fuses supplying the parking and marker lights. If there is a short somewhere, and the PO has replaced the fuse with "whatever was handy" (or, "one that doesn't keep burning out"), the switch and/or wiring will be the thing to go.
 
Got my new (although not quite correct) switch.
Pins are different as expected.
New has no H pin and no D, but has V, old has an H and D but no V.
Now, to figure what what each pin does and hook up my wires accordingly, maybe it's as simple as extracting the terminals from the connector and reinserting where needed?
newandold.jpg


I've also taken some shots of the melted wires, brown jumper took it hard as did the lt/blue/red (which runs to the lighting relay). In this gallery here:
http://gallery.me.com/jvandyke#100414/SDC10770&bgcolor=black

Here's what I know;
Old switch;
pin H is green wire to high/low beam selector
pin L is black wire to ignition switch (with brown jumper to over to pin U (melted one)
pin I is LtBlue/Red wire to lighting relay #30
pin D is white wire to fuse #9 then out to both headlight relays via LtBlue/white and Lt/Blue (position 87)
pin T is Lt/Blue to lighting relay (87A) and also to fuse #15 then out as Green/White to headlight motors

If I knew what year switch I got, I could cross reference it, yes?
Or deduce it logically which hurts my head.
 
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IF you can cut apart the old switch and extract the pins without damaging them, I'd personally do that & transfer to the replacement switch. Easier than rewiring, I reckon.:grin:
 
If you ohm out which pins are connected to which for each of the three switch position (on your "new" switch, that is), I am sure someone here can figure out how it gets connected to the car harness.

Also, post what wire colors go to your headlight switch.
 
Hussein got me thinking;
I didn't really want to but I broke into the new switch. It was 'opposite" of the old one in that pins L and V were internally connected on the old switch and it was I and D that were internally connected on the new one. Old switch; I and D were two separate internally, New: L and V.
Long story short, I pulled the spade pins out of the new switch and rearranged them to match the old one, was pretty easy actually.
Threw it in the car and it works fine although I still have to clean up those wires and I felt a bit of heat when holding the thing in my hand, so I have some careful checking to do.
pretty easy really to make one switch into the other, better than paying $125 for one.

I had already transferred another pin so now this switch has like 8 hanging out the back two not connected to anything and I pity the poor guy who has to figure out what I've done to get by.....I'll leave a note attached.
 
good job jeff...

...I surmise you're capable of figuring out differences in the switches.
But swapping the spring loaded dealy inside is easier, IMHO.

As for the heat generation in new switch, that's worrisome.
As others have said, verify integrity of entire circuit.
Plus, double verify the relay mod.
My seriously brilliant buddy crossed up something on his relay mod,
so if he can do it, anyone can.
Sadly, fried two Bertone switches in the process,
which eventually led him back to the relay mod double check,
and the source of the problem.

BTW, enjoy reading your diagnostics process.
Seems obvious you have above average experience
and can apply fundamentals to specifics of X ownership.
 
olerascal said:
...I surmise you're capable of figuring out differences in the switches.
But swapping the spring loaded dealy inside is easier, IMHO.
Click to expand...

By the time I got the new parts, my old switch was too far gone to save anymore. I don't want to loose this one so I have to figure out what the deal is. BTW it fried out before my head light relays so I doubt that's it. I know one parking light is out up front though blinker works, I'll go around the car and check stuff I guess. Right now, if I turn on just the parking lights (key off) the Lt/red wire that runs to the light relay gets very hot quite fast.
 
It is not unheard of for burned out bulbs to become large loads (as opposed to the more common open circuit). I'd start by removing the bulb you know is burned out and see if the symptoms go away.

if I turn on just the parking lights (key off) the Lt/red wire that runs to the light relay gets very hot quite fast.
Click to expand...
Are you talking about the relays that you added, or the factory one in the fuse box?
 
If you're talking lt blue/red

That one appears to be part of a 3-relay circuit that runs the headlight motors. (LEFT HEADLIGHT, RIGHT HEADLIGHT, and LIGHTING relays in the earlier posted schematic.

Verify that fuse 15 and 16 are really 3 amps, because one of them should be blowing if there are ANY shorts in the headlight motor diodes or in the left/right headlight motor relays.

Pull those fuses and see if the wire still gets hot, then report back.
 
Okay, will replace bulb and double check fuses.
I did redo the wires that were melted and at the same time I added an inline fuse as the lt/blue red comes out of the switch, 10amp blew immediately, tried a 20 (because I had nothing smaller) after checking some connections, it blew with in seconds too. Something stinks.
 
If they are indeed 3 amp fuses

and you're blowing a 20 at the switch, see if you can identify the "lighting" relay (possibly right next to the left and right headlight relays?) and pull it. If the fuse still blows, it's either a pinched lt blue/red wire, or maybe a spade terminal has pulled lose below the fuse panel and is shorting things (yeah, that's fun). If it stops blowing, possibly an internal relay failure or a pinched wire/lose spade terminal between the "lighting" relay and fuses 15/16.
 
see if you can identify the "lighting" relay (possibly right next to the left and right headlight relays?) and pull it.
Click to expand...
Agreed, but the same Lt Blue / Red also feeds the parking / marker / license plate / dash lights. (That part is on different pages in the wiring diagrams). Fuses G and H are for all these lights, so try pulling these fuses to see if the problem goes away.
 
15/16 little bitty greenies, I think 3 amp.
I pulled fuse block/relay block and started taking apart the harness, lt.blue /red shows signs of having gotten hot as it is often slightly melted to it's neighbor, no sign of an actual short yet though. I'm running out of fuses fast....
It blows immediately even with the relay pulled.
 
Ran out of 10Amp for my added in line fuse off the switch so I subbed in a 25. This time I heard a snap from over by the fuse/relay area and Fuse G blew, it was an 8. Sounds like I'm now short hunting. POs suck. I took a 26 out of this spot. I suspect the lt.blue/red is shorted in the harness somewhere. I pulled the lt. blue/red off the back of the lighting relay (there is a yellow combined with it there) and I have continuity between that end of lt.blue/red and EVERY fuse, that doesn't seem right.
 
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