'65 Dart No brake lights. Brake light switch failure?

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Stumpy

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So I took the Dart to a shop to have a Dr Diff front disc brake kit put on.

I get it home and no brake lights. All other lights work, just no brake lights. Brake lights fine before it went to shop. Checked the brake light switch and it's as hot as a pistol and the plunger is not quite making contact with the brake pedal strut. I adjusted the brake light switch so it makes contact with the plunger on the switch and it worked. For a while.

I go out today and no brake lights again. Again, all lights work. Just brake lights out. Switch is making good contact. Checked fuse. Checked bulbs. Checked power to switch with tester. All good. The switch is getting power. I can't see any voltage coming out of switch when I stick a voltage tester probe in the back. It get's hot fast when I depress pedal. So I'm guessing a fried switch? I've never had one of these fail but I suppose it could have fried if the shop didn't disconnect it when they did the brakes.

I found a replacement but not quite the same.
https://www.oreillyauto.com/detail/.../a/14636/automotive-car-1965-dodge-dart?pos=1

The current switch has the power out at the back integrated into the switch (original stock?) This one has a tab to stick a connector on.

Any recommendations for a preferred switch? Do I have it wrong?
 
I’ve got a couple and can send you an original if you’d like. Bet the replacements are for 66 and later with different wiring connectors. 65’s are double spaded
 
And it could also be the turn signal seitch as the brake light switch gets power through the turn signal switching
 
I’ve got a couple and can send you an original if you’d like. Bet the replacements are for 66 and later with different wiring connectors. 65’s are double spaded
That’s strange, mine has only one wire coming from the back.
 
And it could also be the turn signal seitch as the brake light switch gets power through the turn signal switching
Wouldn’t the turn signal switch failure make the turn signals not work? The turn lights are working and there is voltage to the brake light switch.
 
Wouldn’t the turn signal switch failure make the turn signals not work? The turn lights are working and there is voltage to the brake light switch.
No this is a common failure. The TS switch can fail and the signals still work but not brake lights. In the 70/ and later cars, this is commonly caused by the integrated hazard switch

Check the "output" of the brake light switch. I believe this is the white at the column TS switch connector. If you have brake light power there, of course pedal depressed, then it's the TS switch

Try working the hazard switch a few times
 
I’ve got a couple and can send you an original if you’d like. Bet the replacements are for 66 and later with different wiring connectors. 65’s are double spaded

I mis-spoke - getting old I suppose. Up through 65 the brake switch had a spade connector and a female barrel connector as shown in the link you posted. Here is my used one

D976B056-AA9A-4793-AFC9-D62FA5190935.jpeg
 
No this is a common failure. The TS switch can fail and the signals still work but not brake lights. In the 70/ and later cars, this is commonly caused by the integrated hazard switch

Check the "output" of the brake light switch. I believe this is the white at the column TS switch connector. If you have brake light power there, of course pedal depressed, then it's the TS switch

Try working the hazard switch a few times

No power on the back of the switch when in any position. 12V Power coming into the switch. No hazards on a 65. I think the switch is fried. I think the shop didn’t disconnect the battery and fried the switch.

I was looking at the wiring diagram on my 65 Dart Service Manual and it doesn’t look to me like the power is routed through the turn signal switch. Maybe different in later cars.

I’m going to try replacing the stop light switch and see if that does the trick.
 
Correct. The brake lamp wire doesn't route thru the turn signal switch in 1965. It did by the time of my 1969 Dart. You can tell because the replaceable plastic cam in later cars has 2 wires on it vs just-plastic in earlier ones. Check rockauto photos.

All the switch does is connects 12 V (always hot input) to the output when the stem is extended. You might remove it and check with an ohmmeter, and insure that neither terminal connects to the bracket (ground) in any position. To go further, the body connector is behind the left kick panel, where you can verify wiring to it and from there to the rear bulb. You can find wiring diagrams linked here. The heat suggests a short to ground right within the switch, but could also be a short circuit anywhere on the downstream wiring. Strange that a short wouldn't blow the fuse.

BTW, adjust the switch position so that it senses brake pedal motion, but doesn't prevent it. The pedal must not bottom-out on the switch. If it does, that might prevent the Master Cylinder from fully retracting which can cause brake lockup (vent port isn't exposed). But, the switch should be close enough that it is assuredly open with pedal up. If not, your battery will run down overnight from the lamp staying on since supply is always hot.
 
So the rear 1157 bulb one filament is the tail lights, the other is the turn and brake. So if your turn signal is corroded or mis aligned it can cause you to have no brake lights and or no turn lights. I actually have that problem right now on my 63 Dart, no brake lights, some times I have turn signals, but if I move the turn indicator just right I can get brake lights.

I need to pull the steering wheel off and see what is what....
 
Looking at the wiring diagram again. It does look like the stop switch power is connected with the turn signal switch. It looks like the wire at the back of the stop switch D4 is activated by releasing the plunger and power goes to the cluster and to the turn switch. I’m still learning to read these and I suck at it. I still don’t understand exactly what the stop light switch is doing here.

In my case I was always getting power from D3 and no power at D4 in any position. I took out the switch and it looks fried. The spring had pulled out and was only working intermittently. I put in a OEM replacement and it works great now.

Thanks to everyone for the help.

image.jpg
 
Okay I think I understand a little better how the stop switch might work on the 65 Dart. On the 65 the rear turn lights are just the brake lights turning off and on. When stop switch plunger is released it sends power to the brake/turn lights regardless of key position. When the key is in the on position. The turn signal switch works to interrupt the juice to the brake light to cause them to blink off and on. So the power for the stop light switch is not coming from the turn signal switch it is coming from the fuse box and split from the stop switch to the brake/turn lights. The turn signal switch power is from a completely different (key on) fuse. I totally believe that a fried turn signal switch would cause the brake lights to not work but in my case it was the fried stop light switch.

Is this right?
 
No you guys are AFU. Here's how they work. The brake light switch gets "hot" power at all times, regardless of ignition switch. When you press the brake, the output (usually white) of the switch goes TO the turn signal switch. When centered, the TS switch routes this power through the switch to both rear lamps.

When turning, the TS switch disconnects one brake light (for the turn) and routes the TS flasher output to the front lamp (of course) and to the rear lamp, on the side meant to signal. The opposite brake lamp is routed from the brake light switch so you have a brake on the "non turn side.

THIS IS HOW ALL VEHICLES work with one set of lamps, unless it is some New fangled transistorized vehicle make recently that I'm not aware of.

Some cars (like my 70RR) with four rear lamps just paralleled them, IE two 1157 combo bulbs on each side, wired to work in unison

Other cars with SEPARATE brake lights (such as cars with amber turn signals in rear, and this started with foreign cars) do NOT use the TS switch connection. They simply run the brake switch straight back to the separate stop lamps, and the amber turn ones are run direct up to the TS switch.
 
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The main problems to look for:

No power, power not reaching proper points at proper times as in switch problems, bad connections, or odd things like a shorted lamp causing power feedback to wrong circuits. Switches can do that too, if the switch contacts start "wandering around" inside

CHECK POWER when calling for "in operation." If flasher won't cycle, try making a jumper with male "spade/ flag" terminals so you can plug a jumper in across the flasher socket.

Test for power TO the brake light switch, and AT BOTH HALVES of the turn signal switch connector. Wiggle the hazard switch, wiggle the TS switch. Determine if brake lamp(s) work on each or one or either side. Get a helper or erect mirrors so you can see the lamps

CHECK sockets for grounding, and remove and clean and inspect AND TEST lamps. Lamps should be 1157 or 1034 or some form similar, with DUAL contacs and OFFSET bayonet pins. TEST the lamps to make sure both filaments light AND that ONLY ONE lights on each contact. (Testing for internally crossed filaments)
 
In the diagram, wire D4, to pin 7 of the TS connector is the output of the stop lamp switch feeding TO the TS switch.
 
HOW HAZARD switches work. I realize that not all cars had them, and that they were optional for a few years, and could be added aftermarket.

A hazard switch, whether OEM dash mount, aftermarket add on, or even 70/ later "in the TS switch" all work sorta the same

You basically have a 4 terminal "hazard" switch, when off, none of the 4 are connected, and when activated, all 4 are connected.
1 terminal receives power from the separate hazard flasher, powered "hot" at all times
2..terminal goes to the brake light switch wire feeding to the TS switch. This is to feed hazard "flash" to both rear lamps and the TS switch has to be centered
3...terminal goes to left front signal lamp
4...termianl goes to right front signal lamp.

So with hazard switch activated, foot OFF the brake, and TS switch centered, all 4 lamps flash
 
In the diagram, wire D4, to pin 7 of the TS connector is the output of the stop lamp switch feeding TO the TS switch.
Okay I get it now. Thanks for that explanation!

So if D3 is power from fuse box and power is always routed through the SL Switch to D4 to the TS switch what is L8 doing?
 
L8 feeds power off to something else. This is a favorite trick--using a connector also for a junction point. Just follow it and see where it goes
 
Of course had I RTFM better I would have found this and it would have explained everything.
9F2CD5B4-F08D-4331-B281-450C9BB2CD67.jpeg
 
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You want to explain this?
I stand corrected. My 1965 Dart manual shows the same, as does my 1965 Chrysler manual. I know the Chrysler plastic turn signal cam is just plastic (PN SM3?, recall similar to my A's), whereas in my 1969 Dart it had two wires to solder (PN SM9?). Anyway, since they do route the wires thru the turn signal, the filament(s) used for the stop lamp must serve dual-purpose for turn signal flashing too, or at least they disable constant stop lamp while the turn signal is flashing. My Chrysler has ~3 bulbs on each side in the rear so it isn't like they ran out of bulbs to use.
 
I thought I had a brain fart LOL. I THOUGHT I knew how these worked. I think the later ones using the separate bulbs was an effort to be "More worldly" or some nonsense. My 98 Ranger had amber separate signals, and when I bought it someone had used one of those aftermarket tow light adapters to convert it back to the combination stop/ signals, and the adapter had gone bad. I got to digging around ???!!!!!???? and here in the cubby was a factory unused tow harness, and the vehicle already had relays, etc to do just that.
 
At least you don't have a Ford Cougar. It was an upscale Mustang, with one feature being multiple rear turn signals bulbs which flashed in sequence to form a moving light. A complicated setup for the 1960's with multiple relays and timers, requiring much skill to restore them today. Might have been tricky hooking up a trailer connector, though few Cougars would tow. Even trickier was a GM convertible with hardtop which stored the top in the trunk, all automated via many relays.
 
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