Headlight switch , is it the cause? or the curse?

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gdizzle

gdizzle

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My 1st post. 1966 Dodge Dart 270. Just bought it. Kid I got it from said lights were working, then one night they just went out. He suspects wiring.

Also none of the instrument lights work, gas gauge does not work, Alt. gauge not working (stuck in middle). Brake lights do work, so do turn indicators, so does reverse lights. But no lights on the front.

So at this point I assume the actual headlights are good, though I have no way to test. I get continuity from head light plug to Bulkhead (engine side).

I have removed headlight switch and I seem to have continuity on some of the terminals, though I dont really know which terminal is what. But the B2 and B1 are giving me continuity when I pull out the knob. I can buy a new switch for $16. But if the breaker has blown inside the switch, I shouldn't get any continuity on any terminals, correct?

Any ideas?
Of note: on the engine side of the bulkhead, I do see melting on the bottom plastic connector which represents (Y or X) the headlamps, and the wire looks to have solder on it? unlike the rest of the wires.
 
Get the headlight load off the switch by using a relay kit. Improves headlight perform as well.
 
Well you sound like you have WAY more troubles than the light switch.

Here's how the early switches work.

B1--B2. This is power in. One, B1 is UNFUSED power for ONLY the headlights, the other B2 is FUSED power coming from the tail fuse. This powers tail, park, and DASH lights

The headlight section is one separate switch, only for the headlights. Power feeds to the switch from the ammeter, a "nice big" wire, goes through the switch AND and internal breaker, and TO the DIMMER switch, where you select hi / low beam, then OUT through the bulkhead connector to the headlights.

There then, are several places for problems

"Rare" is the power source at the ammeter / harness connection but it does happen

More common is deteriorated contacts in the headlight switch connector

Bad switch, itself

Bad connections at the dimmer switch, or bad dimmer switch

Bad connections at the bulkhead connector......one for hi, one for lo beam

Bad GROUND connections at the headlights 'out at' the fender

Bad connections at the headlight connectors

YOU must go through each "point" in the system and find the troubles.

WHAT YOU NEED:

This is for troubleshooting, no exceptions, minimum, "must haves"

Some sort of multimeter

A 12V test lamp

A few alligator clip leads

And a factory service manual including the wiring diagram. You can download these free "for some years."

http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617

And here

http://www.mymopar.com/index.php?pid=31

Also from "MyMopar" are aftermarket diagrams. These are NOT factory diagrams, are not always correct, and don't always show all connectors and options. They ARE however sometimes easier to follow and are at times very useful

66 Dart "MyMopar" diagram

http://www.mymopar.com/downloads/1966/66DartA.jpg

http://www.mymopar.com/downloads/1966/66DartB.jpg



===================================

Here is how the tail / park / dash light stuff works

Look on the two diagrams, "A"

Look at the far left connection on the headlight switch, "IN" which is TAN. This is the OUTPUT of the switch for the dash lights. That circuit gets power off the TAIL circuit, goes through the switch, and OUT on the TAN. The TAN feeds dimmer controlled dash light power down to the fuse panel, to the INstrument fuse, and then out to all dimmer controlled lamps on ORANGE wires. THIS IS the only fuse that operates in this manner

The YELLOW wires coming off the switch at lower left are the DOME light switch. These are the grounding side of the dome light circuit, which goes to the door switches. The light switch, when twisted 'far left" grounds out that yellow to operate the dome lights

Yellow /Tr (yellow with tracer) coming off at far right and going off the page to the right is the PARK lights. These are ONLY on (in older cars) when park lights are on, NOT headlights. When "Ma" changed to 'full time" park lights in? 70? all she did was move the park light wire over to the TAIL light connection!!!

BLACK coming off the top of the switch is going to the TAIL lights.

It is far far better to check these switches "in operation" using VOLTAGE rather than ohms. It is difficult to RELIABLY check a switch with resistance. This is because of the heavy load on the contacts, which can change do to arcing, and so on.

Turn the switch on. Wiggle it. Wiggle the connector. Look for changes in brightness. Take a reading at B2, the tail light power, and another reading on the tail and park terminals and see if the reading is the same. You need to read down into tenths of volts
 
Thanks for all that info. This is great stuff. I have a multimeter, but I do not have the 12v lamp tester. Will get it today. There is corrosion at the bulkhead terminals for the headlight section ,. I sprayed some DeOxit, but no change. On the headlight switch there is a small rust spot at the revit near the B1, which has spread to the terminal as well. Though I just checked continuity across all the terminals, and they are all working strong. So I begin to suspect the dimmer switch? I also need to work on the bulkhead. No idea where I am going to locate a new plastic plug, but maybe I could squeeze some liquid rubber in there to at least stop any arcing that might occur. I also broke one of the terminals which needle nose pliers, so I have to replace that no matter. It was corroded as well. Keep it coming.
 
You have to be sure that the connector for the headlight switch is in good shape. I've had a few that got so hot that they melted and wouldn't hold the terminals in place or with enough continuity.

Always be sure that all of the connections in there are good before installing into dash.
 
Back in Time said:
Be sure to listen to everything 67Dart273 says .This man knows what he is talking about and is very helpful.
Click to expand...

Knows his stuff, thats for sure. Just don't ask about Windows OS..........LOL
 
gdizzle said:
Thanks for all that info. This is great stuff. I have a multimeter, but I do not have the 12v lamp tester. Will get it today. There is corrosion at the bulkhead terminals for the headlight section ,. I sprayed some DeOxit, but no change. On the headlight switch there is a small rust spot at the revit near the B1, which has spread to the terminal as well. Though I just checked continuity across all the terminals, and they are all working strong. So I begin to suspect the dimmer switch? I also need to work on the bulkhead. No idea where I am going to locate a new plastic plug, but maybe I could squeeze some liquid rubber in there to at least stop any arcing that might occur. I also broke one of the terminals which needle nose pliers, so I have to replace that no matter. It was corroded as well. Keep it coming.
Click to expand...

Read this article. It points out the major causes and troubles with the bulkhead connector. You can get replacment terminals, they are known as "Packard 56." I got some here

http://www.clipsandfasteners.com/Packard_56_Series_Male_18_Gauge_Terminals_GM_29654_p/w30c030.htm

You have to be very careful when you order females and get the ones that look EXACTLY like yours. There is a slightly different "GM" type that will not fit the connectors

Mad article:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

As Ron, "Crackedback" suggested, putting relays in the system gets rid of dim headlights, and relieves the electrical strain on several points in the system. I'd get them working, tho, first.
 
For your fuel & temp gages, you should get a modern electronic "voltage limiter" ($25 ebay). Many posts here.

Sounds like you know how to trouble-shoot, so you will work thru it. On both my 64 & 65 A's, I removed the entire dash wiring and cluster and reworked them on the table to repair former hacks. The pins on the cluster's round connector often loosen and need resoldering to the PCB. I totally re-wired the engine bays, using a modern fuse/relay box (search post).

I suggest not bothering the guy who sold you the car. You must expect such issues when you buy a classic car. You will be happier in the long run to avoid quick hack fixes and work thru things methodically. Indeed, might be best to strip the whole dash innards and fix at once rather than pick at it over time.
 
I am finding different gauges of the terminals. Any idea what it should be?
 
You mean the replacement terminals? I would get no14. The ammeter is larger (two of them) but you can solder larger wire into the no14 terminals "the way they are made"
 
ordered the Packard 56, 18g since that what I see on the wiring diagram from the shop manual.
Also ordered a new dimmer switch (foot), along with a new headlight switch.

Having trouble using this 12v lamp tester, connecting to the ground doesnt really give me enough room. and the body of the car doesn't seem to provide any ground? is that right?

Also, if I disconnect at the bulkhead (X Y Z) , the car won't start, no power at all. Is that right? Also connecting bulkhead, but removing headlight switch - car won't start no power.

I hooked up the old headlight switch again, pulled it out so it is on, no lights, but I do see volts at the dimmer wire, and also on the back of the bulkhead. After a few minutes, I went to remove the Headlight switch, IT WAS BURNING HOT on the rheostat. ????

The dimmer plug looks a little melty too. hummm......

I was also able to see under the dash to the Alternator indicator, and the wire has been cut (red). Cant see where it should be running from. Does that go through the bulkhead as well?

so many questions, all I want is the headlights to work so I can drive at night. Calgon take me awayyy
 
gdizzle said:
ordered a new dimmer switch (foot), along with a new headlight switch.
Click to expand...

Ordered? You should be able to waltz right into a parts store and buy them. NAPA should be able to get or have a pigtail for the dimmer, if it's not repairable

gdizzle said:
Having trouble using this 12v lamp tester, connecting to the ground doesnt really give me enough room. and the body of the car doesn't seem to provide any ground? is that right?
Click to expand...

Body should be ground, but you need to get to a "bare" spot. Something like the radio mounting bolts, etc


gdizzle said:
Also, if I disconnect at the bulkhead (X Y Z) , the car won't start, no power at all. Is that right? Also connecting bulkhead, but removing headlight switch - car won't start no power.
Click to expand...

If you remove the section connecting the fuse link and alternator (large black and large red) no you won't have power

gdizzle said:
I hooked up the old headlight switch again, pulled it out so it is on, no lights, but I do see volts at the dimmer wire, and also on the back of the bulkhead. After a few minutes, I went to remove the Headlight switch, IT WAS BURNING HOT on the rheostat. ????
Click to expand...

Depending on what is going on with the dash lamps the hot rheostat is probably normal. Do the dash lights seem to work OK, you twist the knob right, they get dim, left they get "plenty bright?"

"What volts" you get at the dimmer switch? Sounds like you are "nearing" the problem. With the headlights on, TWO of the dimmer switch contacts should be "live," and one "cold." When you cycle the switch, the "dead" terminal should come alive, and one of the other two goes dead.

If that is working, Next place I'd check (because it's easier) is the headlight grounding out on the front support, and the headlight connector itself.

If you have nothing there, but "do" at the dimmer, it's in the bulkhead connector

gdizzle said:
I was also able to see under the dash to the Alternator indicator, and the wire has been cut (red). Cant see where it should be running from. Does that go through the bulkhead as well?
Click to expand...

"It did," there seems to me a couple / three different possibilities

"You might" have what is know as "fleet / taxi" wiring, which was supplied with 60-65 amp optional alternators. This involved running the ammeter / alternator wires through additional grommet(s) separate from the bulkhead connector, and taping off the original red ammeter wire.

"It might" be that someone did a somewhat ammeter bypass, read this:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

A good clear photo of the bulkhead showing the connector and area nearby might be of help
 
this is first time I have tried to put a picture in a post. And I may have overdone it. Now that I take pic, I clearly see both wires have been cut off the Alt. gauge. I do not see any matching wires.
I included the shot of the Fuse box, with the brilliant idea of grounding to one side with a small green wire?
Also a good shot of the Dimmer switch which just came apart. it really wasnt even connected to the switch. And some disconnected wire plugs, which are near the fuse box, appear to be pink or purple wires . and a cut wire again.

Be advised, this guy had a huge Stereo system with wires and power amps and speakers everywhere. he pulled it all out but many wires remain. I am attempting to reconnect the original Radio, but that is bottom of list.
No NAPA here. only AutoZone, Pep and Oreilys. the Headlight switch should be here in an hour.. But I am still doubting that it is the problem. Many thanks. Damn bulkhead pics look upside down?
 

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What I was looking for is additional "hacked" wiring through the firewall, and see none. It is evident that someone has bypassed the ammeter for some reason.

I can't figure, offhand, what that frayed red hanging down by the fuse panel might be

It appears to me that your dimmer switch has fallen apart, LOL
 
So replacing dimmer switch got me the headlights back.
Thanks so much for your help.
Now when I click the dimmer, I hear small squealing noises (I think it is when I am going to brights). I click again and the noise stops, also I'll lose the lights when it squeals. So there is a short, and the dimmer switch connector is very hot. It is also melty (was melty before).
This also matches the melty on the Bulkhead, though at Bulkhead the majority of melty is at Z, sort of melts into Y. I think Y is the High Beams which is the short. So I think in the Bulkhead it is arcing between those two due to melted connector.
I have ordered a new Dimmer switch connector, will be here in an hour. But not sure how I deal with the bulkhead replacement. Also I got my Packard 56 connectors so I am set to fix the bulkhead if possible. Now I guess I do see people saying to drill through the bulkhead and straight wire it. rather not do that, but not sure any other options if I can't find a connector?

I plan on removing entire dash and trying to figure out why no guages work, and why there is no dash light. (Dome light works BTW ... mini-chub)
 
!!!MAN!!! Does not sound good. Pull the headlights and see if it goes away. Install one lamp at a time. It's "possible" that one of the lamps developed an internal short but doubtful.

Does the under-hood wiring look chopped up, melted, damaged, been hot?
 
under the hood the bulk Y - Z definitely looks melty. Most of the other wires all look fine, not chopped. I am not sure what caused the melty. I might hazard a guess that as the Dimmer switch fell apart, it caused a short which would cause melty at the dimmer connection and the bulkhead high beam connection.
I might try to bypass the bulkhead and try to run a long cable out and around just to test it out.

let the games begin
 
Frankly I think the dimmer switch is the result and not the cause.
 
Replaced dimmer connector. Same issue with hi beams, hissing and heat on the wires. Even disconnected the high beam at the bulk head engine side and still get arcing hissing sound. I wonder the wire red is piggy backed on the diagram one feeds dimmer switch with other feeding the hi beam indicator light on the dash. Since dash doesnt work i think maybe something erong. Getting closer.
 
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