68 Charger - still no brakelights. GOT IT!!!!!

Posted By: Gusteve

68 Charger - still no brakelights. GOT IT!!!!! - 07/02/11 04:55 PM

This is driving me crazy.

Recap: No tail-lights, No brake-lights. But my blinkers work fine.

I've attached the wiring diagram. Refer to the Direction Signal Switch Connection block:

Power should come in on "7", "6" and "8" are power back out to the left and right brakelights.

I have 12V coming into "7" on the block (when I press the brake). When pressing the brake I get 12V across 7 & 6, and 7 & 8.

Thinking the problem might be somewhere in the blinker switch itself, I ran a jumper across 7 & 6, and 7 & 8, and pressed the brake. Still nothing. That's the part that stumps me. The blinkers work by 12V coming in on "2", and being routed back out to "6" or "8" (left of right blinker). I can't see why the brakelights would not come on when I apply 12V to 6 or 8 by jumping the 12V available on "7".

I'm assuming everything else in the wiring is OK because my blinkers work. The only real difference with the blinkers is power coming into "2" on the block instead of "7".

I must be fundamentally mis-understanding something here. Any ideas?

Posted By: jbc426

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 05:31 PM

Start by running a test to the rear wiring harness connector using a different known-good 12+ source and verify that it's not your rear wiring harness. That will tell you if your harnes and lighting grounds are ok.

Use a test light to verify power at the source for the brake and tail lamps, if you haven't already.

I'll try and look at the rest of your harness diagram on-line, but if you post it, that would be helpful.

I have had a driver's tail light not work due to a partially melted turnsignal switch contact.

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 05:45 PM

I'll do what you suggested on the rear harness although I've been assuming all that must be fine because the blinkers work. The blinkers use the same circuit on the rear wiring harness as the brakelights. I suppose it's possible than when the blinker is on it's getting some kind of ground through the front turn signal that is not available when only the brakes are pressed. (But I didn't see anything that looked like that I looked at the diagram.)

I've verified power all the way up where it comes in to the turn signal connector, and all is good.

Here's the rest of the diagram. Thanks for any help you can provide.

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 06:10 PM

OK - this just keeps getting stranger.

On the first diagram at the top is the connector for the rear wiring harness. From what I can tell it's like this:

Black (2) is 12V for tailights
Dk Green (3) is 12V for left brakelight
Brown (6) is 12V for right brakelight

At the connector, I get 12V coming in on 3 & 6 when I press the brake. (Or on each of those individually when I hit the blinkers). So I think that eliminates anything to do with the turn signal switch.

I applied 12V to 2,3 and 6 on the connector going back to the brakelights, and got nothing. I connected my ohm meter and noticed that all three of the connections have continuity to ground, and to each other. I'm assuming that's OK since the bulb itself in the tailight goes to ground.

So - if I apply 12V directly myself they do not work, if I step on the brake it's applying 12v in that same spot and it doesn't work. But the Blinkers (which apply 12V at that exact same spot) do work. How can that be?

Posted By: therocks

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 06:11 PM

If the turn and park work the grounds are fine.That wouldnt have the brakess not working.Its 99 % in the switch.You can test it easy by using a known good switch and just connecting it at the plug.That way you dont have to pull the wheel apart.I always have at least one spare switch for my 65.Rocky

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 06:19 PM

Quote:

If the turn and park work the grounds are fine.That wouldnt have the brakess not working.Its 99 % in the switch.You can test it easy by using a known good switch and just connecting it at the plug.That way you dont have to pull the wheel apart.I always have at least one spare switch for my 65.Rocky

Parking lights don't work either - but I wasn't going to attack that until I got the brake lights working. It's probably the same problem.

Since I'm getting 12V at the connector to the rear harness I think I've eliminated the turn signal switch as a possible problem.

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 07:16 PM

And the plot thickens.

I ran 12V directly from the battery to the rear wiring harness and the brakelights work. So I would think I've eliminated the rear harness as the issue.

But - what would be different about running 12V directly from the battery, vs. 12V from the brake pedal switch? (Which is were I was tapping in for 12V to test the harness).

Voltage from the battery was 12V, voltage from the brake pedal switch was about 11.5V. I can't see that making a difference.

Posted By: DAYCLONA

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 08:29 PM

Quote:

If the turn and park work the grounds are fine.That wouldnt have the brakess not working.Its 99 % in the switch.You can test it easy by using a known good switch and just connecting it at the plug.That way you dont have to pull the wheel apart.I always have at least one spare switch for my 65.Rocky

Best advice, just disconnect the harness under the column and plug in a GOOD/NEW switch to eliminate the turnsignal switch,....68-70 B bodies are notorious for brake light problems,.....and as stated, 99% of the time you eventually end up at the turn signal switch after exhausting every other troubleshooting method,....anybody who's ever owned a 68-70 B body for years, has been there at one time or another with brake light issues,.....change the turnsignal switch

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/02/11 08:50 PM

Quote:

Best advice, just disconnect the harness under the column and plug in a GOOD/NEW switch to eliminate the turnsignal switch,....68-70 B bodies are notorious for brake light problems,.....and as stated, 99% of the time you eventually end up at the turn signal switch after exhausting every other troubleshooting method,....anybody who's ever owned a 68-70 B body for years, has been there at one time or another with brake light issues,.....change the turnsignal switch

Well, rats. That would mean I can't drive my car all weekend.

Any suggestions on where to buy the switch and harness? A quick check of Year One shows $145, but I assume it's far cheaper somewhere else. I really hate to spend money guessing at a problem, though. I already have a new $100 headlight switch that I bought last week that it looks like I didn't need.

I'm seriously tempted to rig up a temporary by-pass just so I have brakelights to drive the car this weekend.....

Although, I have to say, it still makes no sense. I disconnected the turn signal switch, and ran the 12v that goes into that connector directly back to the rear wiring harness and the brake lights did not come on. So the turn signal switch should not have been a factor at all.

I had 12v at the rear harness connector when I pressed the brake pedal, but they don't work. When I ran 12V directly from the battery they did work. I just don't get it. The turn signal switch was not connected at all.

Posted By: therocks

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 12:04 AM

If you are using a meter put it on the bench.Get a tet light and see if it lights.The meter can lie to you on voltage.I had a 90s Mopar that wouldnt charge.Folled the flow chart with my meter.Spent 6 hours trying to figure it out.Ended up the wire from the computer tested over 12 volts on a leter.Put a tets light on it and it wouldnt light as it didnt carry enough amperage to turn on the alt or light the light.Spliced a piece of wire in and it charged perfect.Rocky

Posted By: GO_Fish

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 02:32 AM

The brake lights run through the turn signal switch. You can still have turn signal when the brake circuit in the switch fails (IIRC, been a long time).

25 years or so ago, the I lost the brake lights on my '71 Duster. I narrowed the problem to the turn signal switch in the steering column. I can't remember how now, but I did rig a jumper at the turn signal switch, and temporarily fed the brake lights off the front turn signal part of the switch. The brake lights then functioned normally... Only problem was the front turn signals also functioned as brake lights every time I pressed the brake pedal. But I did then have good rear brake lights until I got the turn signal switch replaced.

Posted By: GMP440

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 05:01 AM

Definetly check the wiring harness that runs the length of the steering column. I had that same problem about ten years ago; no stop or turn signals at rear taillights. I discoverd by pressing on the wire harnes on the steering column that the rear turn signals and stoplamps were working. Turned out to be a loos connction at the pigtail.

Posted By: HemiRick

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 05:10 AM

Do your dash lights work? if not check the fuse as dash and brake lights use same fuse.

Posted By: Dart6pak

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 02:50 PM

Check your E brake switch .

Posted By: stumpy

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 05:08 PM

E-brake switch has nothing to do with the brake light circuit. Let's not confuse him any more than he already is.

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 05:19 PM

Quote:

E-brake switch has nothing to do with the brake light circuit. Let's not confuse him any more than he already is.

Thank you. Looking at the wiring diagram I didn't see anything that would make a difference in the e-Brake circuit.

I understand everyone saying that the problem is in the turn signal switch, but that just doesn't jive with what my diagnostics are telling me. If I disconnect the connector from the turn signal switch, and jumper the 12v that goes into that connector directly to the rear wiring harness I still don't have lights.

Today, I think I'll run a jumper right from the fuse box to the rear harness and see what happens. (Again with the turn signal harness disconnected). If that works, then my problem must be upstream between the turn signal switch and the fusebox. (Even though I'm seeing 12V on that circuit exactly where I should be....).

Lastly - any suggestions on where to buy a turn signal switch and harness? I saw one at a place called MegaPartsusa.com for $45, which is far better than the $145 that Year One wants, but I have never heard of that company before.

Thanks

Posted By: RapidRobert

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 07:31 PM

You have fire at 7 at the "in" (body half) of the TS switch connector w brake pressed (white in). W turn signal stalk in neutral w a good TS switch assy/harness then w the 2 halves connected you would have fire at 6 and 8 in the TS half then your halves are plugged together so then out to 3 and 6 in the connnector behind the kick panel & we're positive we're good from there (kick panel connector) downstream rearward because the flashers work. If I'm reading you right & your jumping directly & it works but not when the brake pedal sends fire there via the white wire just double check that your jumper has fire and that it is going in the connector & touching metal. EDIT meant to say that the connectors are plugged in/good contact as you can jump it & good but not when plugged in right?

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 08:23 PM

Quote:

You have fire at 7 at the "in" (body half) of the TS switch connector w brake pressed (white in). W turn signal stalk in neutral w a good TS switch assy/harness then w the 2 halves connected you would have fire at 6 and 8 in the TS half then your halves are plugged together so then out to 3 and 6 in the connnector behind the kick panel & we're positive we're good from there (kick panel connector) downstream rearward because the flashers work. If I'm reading you right & your jumping directly & it works but not when the brake pedal sends fire there via the white wire just double check that your jumper has fire and that it is going in the connector & touching metal. EDIT meant to say that the connectors are plugged in/good contact as you can jump it & good but not when plugged in right?

White wire at 7 has fire when brakes are pressed.
3 & 6 at rear harness have fire when brakes are pressed. (That's why I'm confused - if 3 & 6 have 12V+ the darn lights should work).

Even though 7 has 12V when brakes are pressed, jumpering 7 (white wire) directly to 3 or 6 does not light the lights. Jumpering directly from the battery to 3 or 6 does light them.

Posted By: RapidRobert

Re: 68 Charger - still no brakelights. I'm stumped. - 07/03/11 10:06 PM

Quote:

White wire at 7 has fire when brakes are pressed.
3 & 6 at rear harness have fire when brakes are pressed. (That's why I'm confused - if 3 & 6 have 12V+ the darn lights should work).

Even though 7 has 12V when brakes are pressed, jumpering 7 (white wire) directly to 3 or 6 does not light the lights. Jumpering directly from the battery to 3 or 6 does light them.

that's 3/6 in the forward half of the rear harness connector behind the kick panel that does have fire when pedal pressed but you connect the halves & no br lites as in no continuity from the connector to the rear when you connect them? but from the batt directly to 3/6 in the rear half of the kick panel connector you're good? And w the kick panel connector connected and jumping fire upstream from there to the white wire at the rear half of the dangling TS connector no brake lites?

Posted By: lokalik

Re: 68 Charger - still no brakelights. I'm stumped. - 07/04/11 02:50 PM

have you tried bypassing the brake light switch by disconnecting the wires and jumper the wires to each other? also are your tail light housings grounded. try running a groung wire at the tail light housing to some bare metal.

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/04/11 04:08 PM

Quote:

that's 3/6 in the forward half of the rear harness connector behind the kick panel that does have fire when pedal pressed but you connect the halves & no br lites as in no continuity from the connector to the rear when you connect them?

Correct. Although, it can't be a continuity issue in the connector itself because the blinkers work.

Quote:

but from the batt directly to 3/6 in the rear half of the kick panel connector you're good?

Correct.

Quote:

And w the kick panel connector connected and jumping fire upstream from there to the white wire at the rear half of the dangling TS connector no brake lites?

I have not jumpered up stream to the white wire (7) yet because I was already showing 12V there. But I think that's my next step.

Thinking about this again this morning, it's almost like I'm getting 12V but I'm not getting enough AMPS at the connector (3,6). I've been using a volt-meter for all this testing, not a test-light, so it's not obvious if the Amps are down when comparing the voltage I'm getting from the brakelights, compared to the blinkers (that work fine).

Posted By: 6PakBee

Re: 68 Charger - still no brakelights. I'm stumped. - 07/04/11 11:00 PM

Quote:

If you are using a meter put it on the bench.Get a tet light and see if it lights.The meter can lie to you on voltage.I had a 90s Mopar that wouldnt charge.Folled the flow chart with my meter.Spent 6 hours trying to figure it out.Ended up the wire from the computer tested over 12 volts on a leter.Put a tets light on it and it wouldnt light as it didnt carry enough amperage to turn on the alt or light the light.Spliced a piece of wire in and it charged perfect.Rocky

Are you using a digital voltmeter rather than a test light? If you are I agree with Rocky. I've also been bit before with a multimeter that did not draw enough current to identify a poor connection. Use a test light and then see what you get.

Posted By: mopar_man

Re: 68 Charger - still no brakelights. I'm stumped. - 07/04/11 11:57 PM

Your park lights have nothing to do with your signal and brake lights other than a common bulb but on the other filament. if your signal lights are working at the rear of the car your tail lights have ground , your wiring is not an issue on the brake light/signal wire as you have proven that already.
You have two separate issues
park lights

brake lights

They are different circuits going to the rear of the car . do you have park lights on the front ?
I would give no credence to your wiring harness codes as your harness could have been altered.
It should be very easy to confirm your park light circuitry by unplugging from your head light switch ...finding the hot wire and then jumping to the supposedly correct wire as the book says.
If that doesn't work , go back to the trunk and unplug the tailights and jump in with a known 12vs.
remember the park lights are the dull side of the bulb.
Now your brake light,i suspects its the harness plug at the steering column providing you already proved that there is always 12v at the brake switch.
there are not many more things it can be .....its not the bulbs , its not the wires going to the rear. so whats left?
Power to the brake switch , steering column harness plug or the signal switch . nothing else to look for !

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/08/11 02:13 PM

Stupid Stupid Stupid.

I bought a test light. Even though my multi-meter was showing 12V on all the brakelight circuits, the test light didn't light on any of them. I can't believe how much time I wasted because of that stupid meter.

Looks like the problem is in the fuse box. I get 12V (on the light) at the outbound side of the fuse, but the pink wire coming out of the box that drives everything has no power (even thought my stupid meter showed 12V on it).

Should be an easy fix from here....

Posted By: mopar_man

Re: 68 Charger - still no brakelights. I'm stumped. - 07/08/11 09:54 PM

well hope thats the trouble, and yes you can have 12v on your meter but very very low amperage which is why stuff don't work. maybe some corrosion on that wire .
good luck

Posted By: Gusteve

Re: 68 Charger - still no brakelights. I'm stumped. - 07/08/11 11:32 PM

Quote:

well hope thats the trouble, and yes you can have 12v on your meter but very very low amperage which is why stuff don't work. maybe some corrosion on that wire .
good luck

That was it. Corrosion on the terminal that the outbound side of the fuse plugged into. Hit it with a small wire wheel on a dremel, added a little solder to the connection and everything WORKS. Brakelights, parking lights, everything.

That was the FIRST THING that I checked when I was trying to diagnose the problem. I had no idea that my multi-meter could show 12V but the circuit itself was dead. Gar!!!!!! I always thought test lights were for dudes that didn't know how to use a meter. Joke's on me.

Worse - I had disassembled a lot of stuff downstream. I just finished re-installing my dash cluster after I realized I could not remount the headlight switch without pulling the cluster out.

Good news is I'm all good to go.

Thanks as always for everyone's help. And particularly the guys that said my multi-meter could lie, that I didn't pay attention to.....

Lesson learned.

Posted By: rustbuckett68

Re: 68 Charger - still no brakelights. I'm stumped. - 07/09/11 03:04 AM

Test light.

Attached picture 6720319-DSCF0888.JPG

Posted By: MoparMarq

Re: 68 Charger - still no brakelights. I'm stumped. - 07/09/11 03:42 AM

Quote:

Quote:

well hope thats the trouble, and yes you can have 12v on your meter but very very low amperage which is why stuff don't work. maybe some corrosion on that wire .
good luck

And particularly the guys that said my multi-meter could lie, that I didn't pay attention to..... Lesson learned.

A good reminder for all of us...Thanks.

Posted By: RapidRobert

Re: 68 Charger - still no brakelights. I'm stumped. - 07/09/11 05:48 AM

Quote:

A good reminder for all of us...Thanks.

I learn't sumpin today, I had no idea & always figured if the meter showed 12V then it was hot

Posted By: mopar_man

Re: 68 Charger - still no brakelights. I'm stumped. - 07/09/11 12:00 PM

Quote:

Quote:

A good reminder for all of us...Thanks.

I learn't sumpin today, I had no idea & always figured if the meter showed 12V then it was hot

Well most times you have 12v showing on a meter, chances are you have a good lead. but sometimes as in Gus's case he had 12 v but not amperage . Something like lightning, billions of volts but very little amperage , if lightning had amperage on a decent ratio of the volts it would destroy everything in its path. just like bombing .
About a decade ago up here in newfoundland , an energy bust of some sort struck a community on Bell Island not far from where i live. It was a clear sunny day so I guess it wasn't lightning , but it dug trenches in the earth just like an excavator, blew up every electrical device around the area, blew the electrical meter right off the houses, killed pets and live stock. One little kid was riding his bike in the middle of it and luckly never got hurt but said there was balls of fire about as big as a beach ball going down the street slowly and about 4 ft off the ground.
Some people said it was the US testing its light beam gun or something. Military never siad much about it .Hmmmmmmm.

Posted By: 6PakBee

Re: 68 Charger - still no brakelights. I'm stumped. - 07/10/11 02:49 AM

Glad you found the problem.

BTW, sometimes us old farts like Rocky and me do know something!

Posted By: GO_Fish

Re: 68 Charger - still no brakelights. I'm stumped. - 07/10/11 04:37 AM

Quote:

Quote:

A good reminder for all of us...Thanks.

I learn't sumpin today, I had no idea & always figured if the meter showed 12V then it was hot

Me 3. I have a test light, but always reach for the voltmeter first. I'll know better now!